diff mbox

[v3,1/4] pinctrl: aspeed: Read and write bits in LPC and GFX controllers

Message ID 20161206031152.3004-2-andrew@aj.id.au
State New
Headers show

Commit Message

Andrew Jeffery Dec. 6, 2016, 3:11 a.m. UTC
The System Control Unit IP block in the Aspeed SoCs is typically where
the pinmux configuration is found, but not always. A number of pins
depend on state in one of LPC Host Control (LHC) or SoC Display
Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
means to adjust these as necessary.

We use syscon to cast a regmap over the GFX and LPC blocks, which is
used as an arbitration layer between the relevant driver and the pinctrl
subsystem. The regmaps are then exposed to the SoC-specific pinctrl
drivers by phandles in the devicetree, and are selected during a mux
request by querying a new 'ip' member in struct aspeed_sig_desc.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
---
 .../devicetree/bindings/pinctrl/pinctrl-aspeed.txt |  50 ++++++-
 drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c         |  18 +--
 drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c         |  48 ++++--
 drivers/pinctrl/aspeed/pinctrl-aspeed.c            | 161 +++++++++++++--------
 drivers/pinctrl/aspeed/pinctrl-aspeed.h            |  32 ++--
 5 files changed, 214 insertions(+), 95 deletions(-)

Comments

Joel Stanley Dec. 8, 2016, 2:19 a.m. UTC | #1
On Tue, Dec 6, 2016 at 1:41 PM, Andrew Jeffery <andrew@aj.id.au> wrote:
> The System Control Unit IP block in the Aspeed SoCs is typically where
> the pinmux configuration is found, but not always. A number of pins
> depend on state in one of LPC Host Control (LHC) or SoC Display
> Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
> means to adjust these as necessary.
>
> We use syscon to cast a regmap over the GFX and LPC blocks, which is
> used as an arbitration layer between the relevant driver and the pinctrl
> subsystem. The regmaps are then exposed to the SoC-specific pinctrl
> drivers by phandles in the devicetree, and are selected during a mux
> request by querying a new 'ip' member in struct aspeed_sig_desc.
>
> Signed-off-by: Andrew Jeffery <andrew@aj.id.au>

Reviewed-by: Joel Stanley <joel@jms.id.au>

(I think I've reviewed these on the openbmc list; feel free to keep my
reviewed-by tag when that's happened).

We might need to split the bindings update and the code changes into
separate patches so they can go via their respective trees.

Cheers,

Joel

> ---
>  .../devicetree/bindings/pinctrl/pinctrl-aspeed.txt |  50 ++++++-
>  drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c         |  18 +--
>  drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c         |  48 ++++--
>  drivers/pinctrl/aspeed/pinctrl-aspeed.c            | 161 +++++++++++++--------
>  drivers/pinctrl/aspeed/pinctrl-aspeed.h            |  32 ++--
>  5 files changed, 214 insertions(+), 95 deletions(-)
>
> diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> index 2ad18c4ea55c..115b0cce6c1c 100644
> --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> @@ -4,12 +4,19 @@ Aspeed Pin Controllers
>  The Aspeed SoCs vary in functionality inside a generation but have a common mux
>  device register layout.
>
> -Required properties:
> -- compatible : Should be any one of the following:
> -               "aspeed,ast2400-pinctrl"
> -               "aspeed,g4-pinctrl"
> -               "aspeed,ast2500-pinctrl"
> -               "aspeed,g5-pinctrl"
> +Required properties for g4:
> +- compatible :                         Should be any one of the following:
> +                               "aspeed,ast2400-pinctrl"
> +                               "aspeed,g4-pinctrl"
> +
> +Required properties for g5:
> +- compatible :                         Should be any one of the following:
> +                               "aspeed,ast2500-pinctrl"
> +                               "aspeed,g5-pinctrl"
> +
> +- aspeed,external-nodes:       A cell of phandles to external controller nodes:
> +                               0: compatible with "aspeed,ast2500-gfx", "syscon"
> +                               1: compatible with "aspeed,ast2500-lpchc", "syscon"
>
>  The pin controller node should be a child of a syscon node with the required
>  property:
> @@ -47,7 +54,7 @@ RGMII1 RGMII2 RMII1 RMII2 SD1 SPI1 SPI1DEBUG SPI1PASSTHRU TIMER4 TIMER5 TIMER6
>  TIMER7 TIMER8 VGABIOSROM
>
>
> -Examples:
> +g4 Example:
>
>  syscon: scu@1e6e2000 {
>         compatible = "syscon", "simple-mfd";
> @@ -63,5 +70,34 @@ syscon: scu@1e6e2000 {
>         };
>  };
>
> +g5 Example:
> +
> +apb {
> +       gfx: display@1e6e6000 {
> +               compatible = "aspeed,ast2500-gfx", "syscon";
> +               reg = <0x1e6e6000 0x1000>;
> +       };
> +
> +       lpchc: lpchc@1e7890a0 {
> +               compatible = "aspeed,ast2500-lpchc", "syscon";
> +               reg = <0x1e7890a0 0xc4>;
> +       };
> +
> +       syscon: scu@1e6e2000 {
> +               compatible = "syscon", "simple-mfd";
> +               reg = <0x1e6e2000 0x1a8>;
> +
> +               pinctrl: pinctrl {
> +                       compatible = "aspeed,g5-pinctrl";
> +                       aspeed,external-nodes = <&gfx, &lpchc>;
> +
> +                       pinctrl_i2c3_default: i2c3_default {
> +                               function = "I2C3";
> +                               groups = "I2C3";
> +                       };
> +               };
> +       };
> +};
> +
>  Please refer to pinctrl-bindings.txt in this directory for details of the
>  common pinctrl bindings used by client devices.
> diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c b/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c
> index a21b071ff290..558bd102416c 100644
> --- a/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c
> +++ b/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c
> @@ -292,7 +292,7 @@ SSSF_PIN_DECL(U18, GPIOG7, FLWP, SIG_DESC_SET(SCU84, 7));
>  #define UART6_DESC     SIG_DESC_SET(SCU90, 7)
>  #define ROM16_DESC     SIG_DESC_SET(SCU90, 6)
>  #define FLASH_WIDE     SIG_DESC_SET(HW_STRAP1, 4)
> -#define BOOT_SRC_NOR   { HW_STRAP1, GENMASK(1, 0), 0, 0 }
> +#define BOOT_SRC_NOR   { ASPEED_IP_SCU, HW_STRAP1, GENMASK(1, 0), 0, 0 }
>
>  #define A8 56
>  SIG_EXPR_DECL(ROMD8, ROM16, ROM16_DESC);
> @@ -418,9 +418,9 @@ FUNC_GROUP_DECL(I2C8, G5, F3);
>  #define U1 88
>  SSSF_PIN_DECL(U1, GPIOL0, NCTS1, SIG_DESC_SET(SCU84, 16));
>
> -#define VPI18_DESC     { SCU90, GENMASK(5, 4), 1, 0 }
> -#define VPI24_DESC     { SCU90, GENMASK(5, 4), 2, 0 }
> -#define VPI30_DESC     { SCU90, GENMASK(5, 4), 3, 0 }
> +#define VPI18_DESC     { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 1, 0 }
> +#define VPI24_DESC     { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 2, 0 }
> +#define VPI30_DESC     { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 3, 0 }
>
>  #define T5 89
>  #define T5_DESC         SIG_DESC_SET(SCU84, 17)
> @@ -641,11 +641,11 @@ SSSF_PIN_DECL(Y22, GPIOR2, ROMCS3, SIG_DESC_SET(SCU88, 26));
>  #define U19 139
>  SSSF_PIN_DECL(U19, GPIOR3, ROMCS4, SIG_DESC_SET(SCU88, 27));
>
> -#define VPOOFF0_DESC   { SCU94, GENMASK(1, 0), 0, 0 }
> -#define VPO12_DESC     { SCU94, GENMASK(1, 0), 1, 0 }
> -#define VPO24_DESC     { SCU94, GENMASK(1, 0), 2, 0 }
> -#define VPOOFF1_DESC   { SCU94, GENMASK(1, 0), 3, 0 }
> -#define VPO_OFF_12      { SCU94, 0x2, 0, 0 }
> +#define VPOOFF0_DESC   { ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 0, 0 }
> +#define VPO12_DESC     { ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 1, 0 }
> +#define VPO24_DESC     { ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 2, 0 }
> +#define VPOOFF1_DESC   { ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 3, 0 }
> +#define VPO_OFF_12      { ASPEED_IP_SCU, SCU94, 0x2, 0, 0 }
>  #define VPO_24_OFF      SIG_DESC_SET(SCU94, 1)
>
>  #define V21 140
> diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c b/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c
> index 87b46390b695..c5c9a1b6fa1c 100644
> --- a/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c
> +++ b/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c
> @@ -10,6 +10,7 @@
>  #include <linux/init.h>
>  #include <linux/io.h>
>  #include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
>  #include <linux/mutex.h>
>  #include <linux/of.h>
>  #include <linux/platform_device.h>
> @@ -26,8 +27,8 @@
>
>  #define ASPEED_G5_NR_PINS 228
>
> -#define COND1          { SCU90, BIT(6), 0, 0 }
> -#define COND2          { SCU94, GENMASK(1, 0), 0, 0 }
> +#define COND1          { ASPEED_IP_SCU, SCU90, BIT(6), 0, 0 }
> +#define COND2          { ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 0, 0 }
>
>  #define B14 0
>  SSSF_PIN_DECL(B14, GPIOA0, MAC1LINK, SIG_DESC_SET(SCU80, 0));
> @@ -186,9 +187,12 @@ MS_PIN_DECL(C20, GPIOE1, NDCD3, GPIE0OUT);
>
>  FUNC_GROUP_DECL(GPIE0, B20, C20);
>
> -#define SPI1_DESC              { HW_STRAP1, GENMASK(13, 12), 1, 0 }
> -#define SPI1DEBUG_DESC         { HW_STRAP1, GENMASK(13, 12), 2, 0 }
> -#define SPI1PASSTHRU_DESC      { HW_STRAP1, GENMASK(13, 12), 3, 0 }
> +#define SPI1_DESC \
> +       { ASPEED_IP_SCU, HW_STRAP1, GENMASK(13, 12), 1, 0 }
> +#define SPI1DEBUG_DESC \
> +       { ASPEED_IP_SCU, HW_STRAP1, GENMASK(13, 12), 2, 0 }
> +#define SPI1PASSTHRU_DESC \
> +       { ASPEED_IP_SCU, HW_STRAP1, GENMASK(13, 12), 3, 0 }
>
>  #define C18 64
>  SIG_EXPR_DECL(SYSCS, SPI1DEBUG, COND1, SPI1DEBUG_DESC);
> @@ -325,10 +329,11 @@ SS_PIN_DECL(R1, GPIOK7, SDA8);
>
>  FUNC_GROUP_DECL(I2C8, P2, R1);
>
> -#define VPIOFF0_DESC    { SCU90, GENMASK(5, 4), 0, 0 }
> -#define VPIOFF1_DESC    { SCU90, GENMASK(5, 4), 1, 0 }
> -#define VPI24_DESC      { SCU90, GENMASK(5, 4), 2, 0 }
> -#define VPIRSVD_DESC    { SCU90, GENMASK(5, 4), 3, 0 }
> +#define VPIOFF0_DESC    { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 0, 0 }
> +#define VPIOFF1_DESC    { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 1, 0 }
> +#define VPI24_DESC      { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 2, 0 }
> +#define VPIRSVD_DESC    { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 3, 0 }
> +
>
>  #define V2 104
>  #define V2_DESC         SIG_DESC_SET(SCU88, 0)
> @@ -848,10 +853,35 @@ static struct pinctrl_desc aspeed_g5_pinctrl_desc = {
>  static int aspeed_g5_pinctrl_probe(struct platform_device *pdev)
>  {
>         int i;
> +       struct regmap *map;
> +       struct device_node *node;
>
>         for (i = 0; i < ARRAY_SIZE(aspeed_g5_pins); i++)
>                 aspeed_g5_pins[i].number = i;
>
> +       node = of_parse_phandle(pdev->dev.of_node, "aspeed,external-nodes", 0);
> +       map = syscon_node_to_regmap(node);
> +       of_node_put(node);
> +       if (IS_ERR(map)) {
> +               dev_warn(&pdev->dev, "No GFX phandle found, some mux configurations may fail\n");
> +               map = NULL;
> +       }
> +       aspeed_g5_pinctrl_data.maps[ASPEED_IP_GFX] = map;
> +
> +       node = of_parse_phandle(pdev->dev.of_node, "aspeed,external-nodes", 1);
> +       if (node) {
> +               map = syscon_node_to_regmap(node->parent);
> +               if (IS_ERR(map)) {
> +                       dev_warn(&pdev->dev, "LHC parent is not a syscon, some mux configurations may fail\n");
> +                       map = NULL;
> +               }
> +       } else {
> +               dev_warn(&pdev->dev, "No LHC phandle found, some mux configurations may fail\n");
> +               map = NULL;
> +       }
> +       of_node_put(node);
> +       aspeed_g5_pinctrl_data.maps[ASPEED_IP_LPC] = map;
> +
>         return aspeed_pinctrl_probe(pdev, &aspeed_g5_pinctrl_desc,
>                         &aspeed_g5_pinctrl_data);
>  }
> diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.c b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
> index 49aeba912531..782c5c97f853 100644
> --- a/drivers/pinctrl/aspeed/pinctrl-aspeed.c
> +++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
> @@ -14,6 +14,12 @@
>  #include "../core.h"
>  #include "pinctrl-aspeed.h"
>
> +static const char *const aspeed_pinmux_ips[] = {
> +       [ASPEED_IP_SCU] = "SCU",
> +       [ASPEED_IP_GFX] = "GFX",
> +       [ASPEED_IP_LPC] = "LPC",
> +};
> +
>  int aspeed_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
>  {
>         struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
> @@ -78,7 +84,8 @@ int aspeed_pinmux_get_fn_groups(struct pinctrl_dev *pctldev,
>  static inline void aspeed_sig_desc_print_val(
>                 const struct aspeed_sig_desc *desc, bool enable, u32 rv)
>  {
> -       pr_debug("SCU%x[0x%08x]=0x%x, got 0x%x from 0x%08x\n", desc->reg,
> +       pr_debug("Want %s%X[0x%08X]=0x%X, got 0x%X from 0x%08X\n",
> +                       aspeed_pinmux_ips[desc->ip], desc->reg,
>                         desc->mask, enable ? desc->enable : desc->disable,
>                         (rv & desc->mask) >> __ffs(desc->mask), rv);
>  }
> @@ -88,10 +95,11 @@ static inline void aspeed_sig_desc_print_val(
>   *
>   * @desc: The signal descriptor of interest
>   * @enabled: True to query the enabled state, false to query disabled state
> - * @regmap: The SCU regmap instance
> + * @regmap: The IP block's regmap instance
>   *
> - * @return True if the descriptor's bitfield is configured to the state
> - * selected by @enabled, false otherwise
> + * @return 1 if the descriptor's bitfield is configured to the state
> + * selected by @enabled, 0 if not, and less than zero if an unrecoverable
> + * failure occurred
>   *
>   * Evaluation of descriptor state is non-trivial in that it is not a binary
>   * outcome: The bitfields can be greater than one bit in size and thus can take
> @@ -99,14 +107,19 @@ static inline void aspeed_sig_desc_print_val(
>   * descriptor (typically this means a different function to the one of interest
>   * is enabled). Thus we must explicitly test for either condition as required.
>   */
> -static bool aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
> +static int aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
>                                  bool enabled, struct regmap *map)
>  {
> +       int ret;
>         unsigned int raw;
>         u32 want;
>
> -       if (regmap_read(map, desc->reg, &raw) < 0)
> -               return false;
> +       if (!map)
> +               return -ENODEV;
> +
> +       ret = regmap_read(map, desc->reg, &raw);
> +       if (ret)
> +               return ret;
>
>         aspeed_sig_desc_print_val(desc, enabled, raw);
>         want = enabled ? desc->enable : desc->disable;
> @@ -119,10 +132,10 @@ static bool aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
>   *
>   * @expr: An expression controlling the signal for a mux function on a pin
>   * @enabled: True to query the enabled state, false to query disabled state
> - * @regmap: The SCU regmap instance
> + * @maps: The list of regmap instances
>   *
> - * @return True if the expression composed by @enabled evaluates true, false
> - * otherwise
> + * @return 1 if the expression composed by @enabled evaluates true, 0 if not,
> + * and less than zero if an unrecoverable failure occurred.
>   *
>   * A mux function is enabled or disabled if the function's signal expression
>   * for each pin in the function's pin group evaluates true for the desired
> @@ -135,19 +148,21 @@ static bool aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
>   * neither the enabled nor disabled state. Thus we must explicitly test for
>   * either condition as required.
>   */
> -static bool aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
> -                                bool enabled, struct regmap *map)
> +static int aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
> +                                bool enabled, struct regmap * const *maps)
>  {
>         int i;
> +       int ret;
>
>         for (i = 0; i < expr->ndescs; i++) {
>                 const struct aspeed_sig_desc *desc = &expr->descs[i];
>
> -               if (!aspeed_sig_desc_eval(desc, enabled, map))
> -                       return false;
> +               ret = aspeed_sig_desc_eval(desc, enabled, maps[desc->ip]);
> +               if (ret <= 0)
> +                       return ret;
>         }
>
> -       return true;
> +       return 1;
>  }
>
>  /**
> @@ -158,19 +173,24 @@ static bool aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
>   *        configured
>   * @enable: true to enable an function's signal through a pin's signal
>   *          expression, false to disable the function's signal
> - * @map: The SCU's regmap instance for pinmux register access.
> + * @maps: The list of regmap instances for pinmux register access.
>   *
> - * @return true if the expression is configured as requested, false otherwise
> + * @return 0 if the expression is configured as requested and a negative error
> + * code otherwise
>   */
> -static bool aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
> -                               bool enable, struct regmap *map)
> +static int aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
> +                               bool enable, struct regmap * const *maps)
>  {
> +       int ret;
>         int i;
>
>         for (i = 0; i < expr->ndescs; i++) {
> -               bool ret;
>                 const struct aspeed_sig_desc *desc = &expr->descs[i];
>                 u32 pattern = enable ? desc->enable : desc->disable;
> +               u32 val = (pattern << __ffs(desc->mask));
> +
> +               if (!maps[desc->ip])
> +                       return -ENODEV;
>
>                 /*
>                  * Strap registers are configured in hardware or by early-boot
> @@ -179,64 +199,79 @@ static bool aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
>                  * deconfigured and is the reason we re-evaluate after writing
>                  * all descriptor bits.
>                  */
> -               if (desc->reg == HW_STRAP1 || desc->reg == HW_STRAP2)
> +               if ((desc->reg == HW_STRAP1 || desc->reg == HW_STRAP2) &&
> +                               desc->ip == ASPEED_IP_SCU)
>                         continue;
>
> -               ret = regmap_update_bits(map, desc->reg, desc->mask,
> -                               pattern << __ffs(desc->mask)) == 0;
> +               ret = regmap_update_bits(maps[desc->ip], desc->reg,
> +                                        desc->mask, val);
>
> -               if (!ret)
> +               if (ret)
>                         return ret;
>         }
>
> -       return aspeed_sig_expr_eval(expr, enable, map);
> +       ret = aspeed_sig_expr_eval(expr, enable, maps);
> +       if (ret < 0)
> +               return ret;
> +
> +       if (!ret)
> +               return -EPERM;
> +
> +       return 0;
>  }
>
> -static bool aspeed_sig_expr_enable(const struct aspeed_sig_expr *expr,
> -                                  struct regmap *map)
> +static int aspeed_sig_expr_enable(const struct aspeed_sig_expr *expr,
> +                                  struct regmap * const *maps)
>  {
> -       if (aspeed_sig_expr_eval(expr, true, map))
> -               return true;
> +       int ret;
> +
> +       ret = aspeed_sig_expr_eval(expr, true, maps);
> +       if (ret < 0)
> +               return ret;
>
> -       return aspeed_sig_expr_set(expr, true, map);
> +       if (!ret)
> +               return aspeed_sig_expr_set(expr, true, maps);
> +
> +       return 0;
>  }
>
> -static bool aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
> -                                   struct regmap *map)
> +static int aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
> +                                   struct regmap * const *maps)
>  {
> -       if (!aspeed_sig_expr_eval(expr, true, map))
> -               return true;
> +       int ret;
> +
> +       ret = aspeed_sig_expr_eval(expr, true, maps);
> +       if (ret < 0)
> +               return ret;
> +
> +       if (ret)
> +               return aspeed_sig_expr_set(expr, false, maps);
>
> -       return aspeed_sig_expr_set(expr, false, map);
> +       return 0;
>  }
>
>  /**
>   * Disable a signal on a pin by disabling all provided signal expressions.
>   *
>   * @exprs: The list of signal expressions (from a priority level on a pin)
> - * @map: The SCU's regmap instance for pinmux register access.
> + * @maps: The list of regmap instances for pinmux register access.
>   *
> - * @return true if all expressions in the list are successfully disabled, false
> - * otherwise
> + * @return 0 if all expressions are disabled, otherwise a negative error code
>   */
> -static bool aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
> -                              struct regmap *map)
> +static int aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
> +                              struct regmap * const *maps)
>  {
> -       bool disabled = true;
> +       int ret = 0;
>
>         if (!exprs)
>                 return true;
>
> -       while (*exprs) {
> -               bool ret;
> -
> -               ret = aspeed_sig_expr_disable(*exprs, map);
> -               disabled = disabled && ret;
> -
> +       while (*exprs && !ret) {
> +               ret = aspeed_sig_expr_disable(*exprs, maps);
>                 exprs++;
>         }
>
> -       return disabled;
> +       return ret;
>  }
>
>  /**
> @@ -330,6 +365,7 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
>                           unsigned int group)
>  {
>         int i;
> +       int ret;
>         const struct aspeed_pinctrl_data *pdata =
>                 pinctrl_dev_get_drvdata(pctldev);
>         const struct aspeed_pin_group *pgroup = &pdata->groups[group];
> @@ -343,6 +379,8 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
>                 const struct aspeed_sig_expr **funcs;
>                 const struct aspeed_sig_expr ***prios;
>
> +               pr_debug("Muxing pin %d for %s\n", pin, pfunc->name);
> +
>                 if (!pdesc)
>                         return -EINVAL;
>
> @@ -358,8 +396,9 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
>                         if (expr)
>                                 break;
>
> -                       if (!aspeed_disable_sig(funcs, pdata->map))
> -                               return -EPERM;
> +                       ret = aspeed_disable_sig(funcs, pdata->maps);
> +                       if (ret)
> +                               return ret;
>
>                         prios++;
>                 }
> @@ -377,8 +416,9 @@ int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
>                         return -ENXIO;
>                 }
>
> -               if (!aspeed_sig_expr_enable(expr, pdata->map))
> -                       return -EPERM;
> +               ret = aspeed_sig_expr_enable(expr, pdata->maps);
> +               if (ret)
> +                       return ret;
>         }
>
>         return 0;
> @@ -414,6 +454,7 @@ int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
>                                struct pinctrl_gpio_range *range,
>                                unsigned int offset)
>  {
> +       int ret;
>         const struct aspeed_pinctrl_data *pdata =
>                 pinctrl_dev_get_drvdata(pctldev);
>         const struct aspeed_pin_desc *pdesc = pdata->pins[offset].drv_data;
> @@ -432,8 +473,9 @@ int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
>                 if (aspeed_gpio_in_exprs(funcs))
>                         break;
>
> -               if (!aspeed_disable_sig(funcs, pdata->map))
> -                       return -EPERM;
> +               ret = aspeed_disable_sig(funcs, pdata->maps);
> +               if (ret)
> +                       return ret;
>
>                 prios++;
>         }
> @@ -462,10 +504,7 @@ int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
>          * If GPIO is not the lowest priority signal type, assume there is only
>          * one expression defined to enable the GPIO function
>          */
> -       if (!aspeed_sig_expr_enable(expr, pdata->map))
> -               return -EPERM;
> -
> -       return 0;
> +       return aspeed_sig_expr_enable(expr, pdata->maps);
>  }
>
>  int aspeed_pinctrl_probe(struct platform_device *pdev,
> @@ -481,10 +520,10 @@ int aspeed_pinctrl_probe(struct platform_device *pdev,
>                 return -ENODEV;
>         }
>
> -       pdata->map = syscon_node_to_regmap(parent->of_node);
> -       if (IS_ERR(pdata->map)) {
> +       pdata->maps[ASPEED_IP_SCU] = syscon_node_to_regmap(parent->of_node);
> +       if (IS_ERR(pdata->maps[ASPEED_IP_SCU])) {
>                 dev_err(&pdev->dev, "No regmap for syscon pincontroller parent\n");
> -               return PTR_ERR(pdata->map);
> +               return PTR_ERR(pdata->maps[ASPEED_IP_SCU]);
>         }
>
>         pctl = pinctrl_register(pdesc, &pdev->dev, pdata);
> diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.h b/drivers/pinctrl/aspeed/pinctrl-aspeed.h
> index 3e72ef8c54bf..0e93cbf2ff33 100644
> --- a/drivers/pinctrl/aspeed/pinctrl-aspeed.h
> +++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.h
> @@ -232,6 +232,11 @@
>   * group.
>   */
>
> +#define ASPEED_IP_SCU          0
> +#define ASPEED_IP_GFX          1
> +#define ASPEED_IP_LPC          2
> +#define ASPEED_NR_PINMUX_IPS   3
> +
>  /*
>   * The "Multi-function Pins Mapping and Control" table in the SoC datasheet
>   * references registers by the device/offset mnemonic. The register macros
> @@ -261,7 +266,9 @@
>    * A signal descriptor, which describes the register, bits and the
>    * enable/disable values that should be compared or written.
>    *
> -  * @reg: The register offset from base in bytes
> +  * @ip: The IP block identifier, used as an index into the regmap array in
> +  *      struct aspeed_pinctrl_data
> +  * @reg: The register offset with respect to the base address of the IP block
>    * @mask: The mask to apply to the register. The lowest set bit of the mask is
>    *        used to derive the shift value.
>    * @enable: The value that enables the function. Value should be in the LSBs,
> @@ -270,6 +277,7 @@
>    *           LSBs, not at the position of the mask.
>    */
>  struct aspeed_sig_desc {
> +       unsigned int ip;
>         unsigned int reg;
>         u32 mask;
>         u32 enable;
> @@ -313,24 +321,30 @@ struct aspeed_pin_desc {
>
>  /* Macro hell */
>
> +#define SIG_DESC_IP_BIT(ip, reg, idx, val) \
> +       { ip, reg, BIT_MASK(idx), val, (((val) + 1) & 1) }
> +
>  /**
> - * Short-hand macro for describing a configuration enabled by the state of one
> - * bit. The disable value is derived.
> + * Short-hand macro for describing an SCU descriptor enabled by the state of
> + * one bit. The disable value is derived.
>   *
>   * @reg: The signal's associated register, offset from base
>   * @idx: The signal's bit index in the register
>   * @val: The value (0 or 1) that enables the function
>   */
>  #define SIG_DESC_BIT(reg, idx, val) \
> -       { reg, BIT_MASK(idx), val, (((val) + 1) & 1) }
> +       SIG_DESC_IP_BIT(ASPEED_IP_SCU, reg, idx, val)
> +
> +#define SIG_DESC_IP_SET(ip, reg, idx) SIG_DESC_IP_BIT(ip, reg, idx, 1)
>
>  /**
> - * A further short-hand macro describing a configuration enabled with a set bit.
> + * A further short-hand macro expanding to an SCU descriptor enabled by a set
> + * bit.
>   *
> - * @reg: The configuration's associated register, offset from base
> - * @idx: The configuration's bit index in the register
> + * @reg: The register, offset from base
> + * @idx: The bit index in the register
>   */
> -#define SIG_DESC_SET(reg, idx) SIG_DESC_BIT(reg, idx, 1)
> +#define SIG_DESC_SET(reg, idx) SIG_DESC_IP_BIT(ASPEED_IP_SCU, reg, idx, 1)
>
>  #define SIG_DESC_LIST_SYM(sig, func) sig_descs_ ## sig ## _ ## func
>  #define SIG_DESC_LIST_DECL(sig, func, ...) \
> @@ -500,7 +514,7 @@ struct aspeed_pin_desc {
>         MS_PIN_DECL_(pin, SIG_EXPR_LIST_PTR(gpio))
>
>  struct aspeed_pinctrl_data {
> -       struct regmap *map;
> +       struct regmap *maps[ASPEED_NR_PINMUX_IPS];
>
>         const struct pinctrl_pin_desc *pins;
>         const unsigned int npins;
> --
> 2.9.3
>
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Rob Herring Dec. 12, 2016, 4:27 p.m. UTC | #2
On Tue, Dec 06, 2016 at 02:11:49PM +1100, Andrew Jeffery wrote:
> The System Control Unit IP block in the Aspeed SoCs is typically where
> the pinmux configuration is found, but not always. A number of pins
> depend on state in one of LPC Host Control (LHC) or SoC Display
> Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
> means to adjust these as necessary.
> 
> We use syscon to cast a regmap over the GFX and LPC blocks, which is
> used as an arbitration layer between the relevant driver and the pinctrl
> subsystem. The regmaps are then exposed to the SoC-specific pinctrl
> drivers by phandles in the devicetree, and are selected during a mux
> request by querying a new 'ip' member in struct aspeed_sig_desc.
> 
> Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
> ---
>  .../devicetree/bindings/pinctrl/pinctrl-aspeed.txt |  50 ++++++-
>  drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c         |  18 +--
>  drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c         |  48 ++++--
>  drivers/pinctrl/aspeed/pinctrl-aspeed.c            | 161 +++++++++++++--------
>  drivers/pinctrl/aspeed/pinctrl-aspeed.h            |  32 ++--
>  5 files changed, 214 insertions(+), 95 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> index 2ad18c4ea55c..115b0cce6c1c 100644
> --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> @@ -4,12 +4,19 @@ Aspeed Pin Controllers
>  The Aspeed SoCs vary in functionality inside a generation but have a common mux
>  device register layout.
>  
> -Required properties:
> -- compatible : Should be any one of the following:
> -		"aspeed,ast2400-pinctrl"
> -		"aspeed,g4-pinctrl"
> -		"aspeed,ast2500-pinctrl"
> -		"aspeed,g5-pinctrl"
> +Required properties for g4:
> +- compatible : 			Should be any one of the following:
> +				"aspeed,ast2400-pinctrl"
> +				"aspeed,g4-pinctrl"
> +
> +Required properties for g5:
> +- compatible : 			Should be any one of the following:
> +				"aspeed,ast2500-pinctrl"
> +				"aspeed,g5-pinctrl"
> +
> +- aspeed,external-nodes:	A cell of phandles to external controller nodes:
> +				0: compatible with "aspeed,ast2500-gfx", "syscon"
> +				1: compatible with "aspeed,ast2500-lpchc", "syscon"
>  
>  The pin controller node should be a child of a syscon node with the required
>  property:
> @@ -47,7 +54,7 @@ RGMII1 RGMII2 RMII1 RMII2 SD1 SPI1 SPI1DEBUG SPI1PASSTHRU TIMER4 TIMER5 TIMER6
>  TIMER7 TIMER8 VGABIOSROM
>  
>  
> -Examples:
> +g4 Example:
>  
>  syscon: scu@1e6e2000 {
>  	compatible = "syscon", "simple-mfd";
> @@ -63,5 +70,34 @@ syscon: scu@1e6e2000 {
>  	};
>  };
>  
> +g5 Example:
> +
> +apb {
> +	gfx: display@1e6e6000 {
> +		compatible = "aspeed,ast2500-gfx", "syscon";
> +		reg = <0x1e6e6000 0x1000>;
> +	};
> +
> +	lpchc: lpchc@1e7890a0 {
> +		compatible = "aspeed,ast2500-lpchc", "syscon";
> +		reg = <0x1e7890a0 0xc4>;
> +	};
> +
> +	syscon: scu@1e6e2000 {
> +		compatible = "syscon", "simple-mfd";

I must have missed this the first time, but "syscon" should be used with 
a specific compatible. Though, the scu binding does define one.

> +		reg = <0x1e6e2000 0x1a8>;
> +
> +		pinctrl: pinctrl {

Is this the only child? 

> +			compatible = "aspeed,g5-pinctrl";

There's no register range for pinctrl?

> +			aspeed,external-nodes = <&gfx, &lpchc>;
> +
> +			pinctrl_i2c3_default: i2c3_default {
> +				function = "I2C3";
> +				groups = "I2C3";
> +			};
> +		};
> +	};
> +};
> +
>  Please refer to pinctrl-bindings.txt in this directory for details of the
>  common pinctrl bindings used by client devices.
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Andrew Jeffery Dec. 13, 2016, 6:12 a.m. UTC | #3
On Mon, 2016-12-12 at 10:27 -0600, Rob Herring wrote:
> On Tue, Dec 06, 2016 at 02:11:49PM +1100, Andrew Jeffery wrote:
> > The System Control Unit IP block in the Aspeed SoCs is typically where
> > the pinmux configuration is found, but not always. A number of pins
> > depend on state in one of LPC Host Control (LHC) or SoC Display
> > Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
> > means to adjust these as necessary.
> > 
> > We use syscon to cast a regmap over the GFX and LPC blocks, which is
> > used as an arbitration layer between the relevant driver and the pinctrl
> > subsystem. The regmaps are then exposed to the SoC-specific pinctrl
> > drivers by phandles in the devicetree, and are selected during a mux
> > request by querying a new 'ip' member in struct aspeed_sig_desc.
> > 
> > > > Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
> > ---
> >  .../devicetree/bindings/pinctrl/pinctrl-aspeed.txt |  50 ++++++-
> >  drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c         |  18 +--
> >  drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c         |  48 ++++--
> >  drivers/pinctrl/aspeed/pinctrl-aspeed.c            | 161 +++++++++++++--------
> >  drivers/pinctrl/aspeed/pinctrl-aspeed.h            |  32 ++--
> >  5 files changed, 214 insertions(+), 95 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> > index 2ad18c4ea55c..115b0cce6c1c 100644
> > --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> > +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
> > @@ -4,12 +4,19 @@ Aspeed Pin Controllers
> >  The Aspeed SoCs vary in functionality inside a generation but have a common mux
> >  device register layout.
> >  
> > -Required properties:
> > -- compatible : Should be any one of the following:
> > > > -		"aspeed,ast2400-pinctrl"
> > > > -		"aspeed,g4-pinctrl"
> > > > -		"aspeed,ast2500-pinctrl"
> > > > -		"aspeed,g5-pinctrl"
> > +Required properties for g4:
> > > > +- compatible : 			Should be any one of the following:
> > > > +				"aspeed,ast2400-pinctrl"
> > > > +				"aspeed,g4-pinctrl"
> > +
> > +Required properties for g5:
> > > > +- compatible : 			Should be any one of the following:
> > > > +				"aspeed,ast2500-pinctrl"
> > > > +				"aspeed,g5-pinctrl"
> > +
> > > > +- aspeed,external-nodes:	A cell of phandles to external controller nodes:
> > > > +				0: compatible with "aspeed,ast2500-gfx", "syscon"
> > > > +				1: compatible with "aspeed,ast2500-lpchc", "syscon"
> >  
> >  The pin controller node should be a child of a syscon node with the required
> >  property:
> > @@ -47,7 +54,7 @@ RGMII1 RGMII2 RMII1 RMII2 SD1 SPI1 SPI1DEBUG SPI1PASSTHRU TIMER4 TIMER5 TIMER6
> >  TIMER7 TIMER8 VGABIOSROM
> >  
> >  
> > -Examples:
> > +g4 Example:
> >  
> > > >  syscon: scu@1e6e2000 {
> > > >  	compatible = "syscon", "simple-mfd";
> > > > @@ -63,5 +70,34 @@ syscon: scu@1e6e2000 {
> > > >  	};
> >  };
> >  
> > +g5 Example:
> > +
> > +apb {
> > > > > > +	gfx: display@1e6e6000 {
> > > > +		compatible = "aspeed,ast2500-gfx", "syscon";
> > > > +		reg = <0x1e6e6000 0x1000>;
> > > > +	};
> > +
> > > > > > +	lpchc: lpchc@1e7890a0 {
> > > > +		compatible = "aspeed,ast2500-lpchc", "syscon";
> > > > +		reg = <0x1e7890a0 0xc4>;
> > > > +	};
> > +
> > > > > > +	syscon: scu@1e6e2000 {
> > +		compatible = "syscon", "simple-mfd";
> 
> I must have missed this the first time, but "syscon" should be used with 
> a specific compatible. Though, the scu binding does define one.

Yes, the example should be fixed.

> 
> > > > +		reg = <0x1e6e2000 0x1a8>;
> > +
> > +		pinctrl: pinctrl {
> 
> Is this the only child? 

No. A incomplete list of other functions in the SCU includes:

* An RNG
* Power management
* PCI configuration
* System reset
* Clock configuration

> 
> > +			compatible = "aspeed,g5-pinctrl";
> 
> There's no register range for pinctrl?

This may be a mistake on my part; when I wrote this I had no experience
with writing devicetree bindings (and still don't have a lot).

The SCU does have register regions for pinctrl but on reflection I feel
neither the mfd nor syscon bindings describe how children's resources
should be treated in general. The example in the mfd bindings is for
hardware that is register-bit-led,compatible, whose bindings use the
'offset' property rather than 'reg', which still describes where, but
not using the reg property. Given my uncertainty with reg in an mfd
child, I wrote the pinctrl/pinmux driver using offsets from the base of
the SCU's syscon rather than describing the exact region(s) of the
syscon that should be used.

The issue you raise here occurred to me when writing the LPC Host
Controller bindings, but there I wasn't convinced using the ranges
property to give offsets was the right thing to do either.

Regardless, whilst there are two dedicated regions of pinmux registers,
the mux state also depends on bits in SCU registers outside of these
regions. Assuming we define an appropriate ranges property for the SCU
syscon the pinctrl reg property would look like:

    reg = <0x2c 0x1>, <0x3c 0x1>, <0x48 0x1>, <0x70 0x1>, <0x7c 0x1>, <0x80 0x18>, <0xa0 0x10>, <0xd0 0x1>;

This is the list of registers affecting the mux taken from the pinctrl-
aspeed.h.

What action do you recommend here? The pinctrl dts patches for the
Aspeed SoCs are yet to be applied, so changing the bindings to require
a reg property can't break any existing in-tree users as there are
none. The pinctrl driver can be patched to respect the reg property
after the fact, though actually using the region descriptions might be
interesting.

> 
> > +			aspeed,external-nodes = <&gfx, &lpchc>;

Did you have feedback on this approach? I queried you about it in the
previous revision, but never received a reply:

https://marc.info/?l=devicetree&m=147873554311535&w=4

Thanks,

Andrew

> > +
> > > > +			pinctrl_i2c3_default: i2c3_default {
> > > > +				function = "I2C3";
> > > > +				groups = "I2C3";
> > > > +			};
> > > > +		};
> > > > +	};
> > +};
> > +
> >  Please refer to pinctrl-bindings.txt in this directory for details of the
> >  common pinctrl bindings used by client devices.
Rob Herring Dec. 14, 2016, 4:46 p.m. UTC | #4
On Tue, Dec 13, 2016 at 12:12 AM, Andrew Jeffery <andrew@aj.id.au> wrote:
> On Mon, 2016-12-12 at 10:27 -0600, Rob Herring wrote:
>> On Tue, Dec 06, 2016 at 02:11:49PM +1100, Andrew Jeffery wrote:
>> > The System Control Unit IP block in the Aspeed SoCs is typically where
>> > the pinmux configuration is found, but not always. A number of pins
>> > depend on state in one of LPC Host Control (LHC) or SoC Display
>> > Controller (GFX) IP blocks, so the Aspeed pinmux drivers should have the
>> > means to adjust these as necessary.
>> >
>> > We use syscon to cast a regmap over the GFX and LPC blocks, which is
>> > used as an arbitration layer between the relevant driver and the pinctrl
>> > subsystem. The regmaps are then exposed to the SoC-specific pinctrl
>> > drivers by phandles in the devicetree, and are selected during a mux
>> > request by querying a new 'ip' member in struct aspeed_sig_desc.
>> >
>> > > > Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
>> > ---
>> >  .../devicetree/bindings/pinctrl/pinctrl-aspeed.txt |  50 ++++++-
>> >  drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c         |  18 +--
>> >  drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c         |  48 ++++--
>> >  drivers/pinctrl/aspeed/pinctrl-aspeed.c            | 161 +++++++++++++--------
>> >  drivers/pinctrl/aspeed/pinctrl-aspeed.h            |  32 ++--
>> >  5 files changed, 214 insertions(+), 95 deletions(-)
>> >
>> > diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
>> > index 2ad18c4ea55c..115b0cce6c1c 100644
>> > --- a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
>> > +++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
>> > @@ -4,12 +4,19 @@ Aspeed Pin Controllers
>> >  The Aspeed SoCs vary in functionality inside a generation but have a common mux
>> >  device register layout.
>> >
>> > -Required properties:
>> > -- compatible : Should be any one of the following:
>> > > > -               "aspeed,ast2400-pinctrl"
>> > > > -               "aspeed,g4-pinctrl"
>> > > > -               "aspeed,ast2500-pinctrl"
>> > > > -               "aspeed,g5-pinctrl"
>> > +Required properties for g4:
>> > > > +- compatible :                         Should be any one of the following:
>> > > > +                               "aspeed,ast2400-pinctrl"
>> > > > +                               "aspeed,g4-pinctrl"
>> > +
>> > +Required properties for g5:
>> > > > +- compatible :                         Should be any one of the following:
>> > > > +                               "aspeed,ast2500-pinctrl"
>> > > > +                               "aspeed,g5-pinctrl"
>> > +
>> > > > +- aspeed,external-nodes:       A cell of phandles to external controller nodes:
>> > > > +                               0: compatible with "aspeed,ast2500-gfx", "syscon"
>> > > > +                               1: compatible with "aspeed,ast2500-lpchc", "syscon"
>> >
>> >  The pin controller node should be a child of a syscon node with the required
>> >  property:
>> > @@ -47,7 +54,7 @@ RGMII1 RGMII2 RMII1 RMII2 SD1 SPI1 SPI1DEBUG SPI1PASSTHRU TIMER4 TIMER5 TIMER6
>> >  TIMER7 TIMER8 VGABIOSROM
>> >
>> >
>> > -Examples:
>> > +g4 Example:
>> >
>> > > >  syscon: scu@1e6e2000 {
>> > > >         compatible = "syscon", "simple-mfd";
>> > > > @@ -63,5 +70,34 @@ syscon: scu@1e6e2000 {
>> > > >         };
>> >  };
>> >
>> > +g5 Example:
>> > +
>> > +apb {
>> > > > > > +   gfx: display@1e6e6000 {
>> > > > +               compatible = "aspeed,ast2500-gfx", "syscon";
>> > > > +               reg = <0x1e6e6000 0x1000>;
>> > > > +       };
>> > +
>> > > > > > +   lpchc: lpchc@1e7890a0 {
>> > > > +               compatible = "aspeed,ast2500-lpchc", "syscon";
>> > > > +               reg = <0x1e7890a0 0xc4>;
>> > > > +       };
>> > +
>> > > > > > +   syscon: scu@1e6e2000 {
>> > +           compatible = "syscon", "simple-mfd";
>>
>> I must have missed this the first time, but "syscon" should be used with
>> a specific compatible. Though, the scu binding does define one.
>
> Yes, the example should be fixed.
>
>>
>> > > > +               reg = <0x1e6e2000 0x1a8>;
>> > +
>> > +           pinctrl: pinctrl {
>>
>> Is this the only child?
>
> No. A incomplete list of other functions in the SCU includes:
>
> * An RNG
> * Power management
> * PCI configuration
> * System reset
> * Clock configuration
>
>>
>> > +                   compatible = "aspeed,g5-pinctrl";
>>
>> There's no register range for pinctrl?
>
> This may be a mistake on my part; when I wrote this I had no experience
> with writing devicetree bindings (and still don't have a lot).
>
> The SCU does have register regions for pinctrl but on reflection I feel
> neither the mfd nor syscon bindings describe how children's resources
> should be treated in general. The example in the mfd bindings is for
> hardware that is register-bit-led,compatible, whose bindings use the
> 'offset' property rather than 'reg', which still describes where, but
> not using the reg property. Given my uncertainty with reg in an mfd
> child, I wrote the pinctrl/pinmux driver using offsets from the base of
> the SCU's syscon rather than describing the exact region(s) of the
> syscon that should be used.
>
> The issue you raise here occurred to me when writing the LPC Host
> Controller bindings, but there I wasn't convinced using the ranges
> property to give offsets was the right thing to do either.
>
> Regardless, whilst there are two dedicated regions of pinmux registers,
> the mux state also depends on bits in SCU registers outside of these
> regions. Assuming we define an appropriate ranges property for the SCU
> syscon the pinctrl reg property would look like:
>
>     reg = <0x2c 0x1>, <0x3c 0x1>, <0x48 0x1>, <0x70 0x1>, <0x7c 0x1>, <0x80 0x18>, <0xa0 0x10>, <0xd0 0x1>;
>
> This is the list of registers affecting the mux taken from the pinctrl-
> aspeed.h.

With other registers in the holes, right? If it is sparse like that,
then yes you probably just want to have reg in the parent for the
whole block.

> What action do you recommend here? The pinctrl dts patches for the
> Aspeed SoCs are yet to be applied, so changing the bindings to require
> a reg property can't break any existing in-tree users as there are
> none. The pinctrl driver can be patched to respect the reg property
> after the fact, though actually using the region descriptions might be
> interesting.
>
>>
>> > +                   aspeed,external-nodes = <&gfx, &lpchc>;
>
> Did you have feedback on this approach? I queried you about it in the
> previous revision, but never received a reply:

It seems okay. At least, I don't have a better suggestion.

Rob
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Andrew Jeffery Dec. 15, 2016, midnight UTC | #5
On Wed, 2016-12-14 at 10:46 -0600, Rob Herring wrote:
> >> > +                   compatible = "aspeed,g5-pinctrl";
> >>
> >> There's no register range for pinctrl?
> >
> > This may be a mistake on my part; when I wrote this I had no experience
> > with writing devicetree bindings (and still don't have a lot).
> >
> > The SCU does have register regions for pinctrl but on reflection I feel
> > neither the mfd nor syscon bindings describe how children's resources
> > should be treated in general. The example in the mfd bindings is for
> > hardware that is register-bit-led,compatible, whose bindings use the
> > 'offset' property rather than 'reg', which still describes where, but
> > not using the reg property. Given my uncertainty with reg in an mfd
> > child, I wrote the pinctrl/pinmux driver using offsets from the base of
> > the SCU's syscon rather than describing the exact region(s) of the
> > syscon that should be used.
> >
> > The issue you raise here occurred to me when writing the LPC Host
> > Controller bindings, but there I wasn't convinced using the ranges
> > property to give offsets was the right thing to do either.
> >
> > Regardless, whilst there are two dedicated regions of pinmux registers,
> > the mux state also depends on bits in SCU registers outside of these
> > regions. Assuming we define an appropriate ranges property for the SCU
> > syscon the pinctrl reg property would look like:
> >
> >     reg = <0x2c 0x1>, <0x3c 0x1>, <0x48 0x1>, <0x70 0x1>, <0x7c 0x1>, <0x80 0x18>, <0xa0 0x10>, <0xd0 0x1>;
> >
> > This is the list of registers affecting the mux taken from the pinctrl-
> > aspeed.h.
> 
> With other registers in the holes, right? 

Yes.

> If it is sparse like that,
> then yes you probably just want to have reg in the parent for the
> whole block.

Alright, we will leave it as-is.

> 
> > What action do you recommend here? The pinctrl dts patches for the
> > Aspeed SoCs are yet to be applied, so changing the bindings to require
> > a reg property can't break any existing in-tree users as there are
> > none. The pinctrl driver can be patched to respect the reg property
> > after the fact, though actually using the region descriptions might be
> > interesting.
> >
> >>
> >> > +                   aspeed,external-nodes = <&gfx, &lpchc>;
> >
> > Did you have feedback on this approach? I queried you about it in the
> > previous revision, but never received a reply:
> 
> It seems okay. At least, I don't have a better suggestion.

Thanks.

Andrew
diff mbox

Patch

diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
index 2ad18c4ea55c..115b0cce6c1c 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-aspeed.txt
@@ -4,12 +4,19 @@  Aspeed Pin Controllers
 The Aspeed SoCs vary in functionality inside a generation but have a common mux
 device register layout.
 
-Required properties:
-- compatible : Should be any one of the following:
-		"aspeed,ast2400-pinctrl"
-		"aspeed,g4-pinctrl"
-		"aspeed,ast2500-pinctrl"
-		"aspeed,g5-pinctrl"
+Required properties for g4:
+- compatible : 			Should be any one of the following:
+				"aspeed,ast2400-pinctrl"
+				"aspeed,g4-pinctrl"
+
+Required properties for g5:
+- compatible : 			Should be any one of the following:
+				"aspeed,ast2500-pinctrl"
+				"aspeed,g5-pinctrl"
+
+- aspeed,external-nodes:	A cell of phandles to external controller nodes:
+				0: compatible with "aspeed,ast2500-gfx", "syscon"
+				1: compatible with "aspeed,ast2500-lpchc", "syscon"
 
 The pin controller node should be a child of a syscon node with the required
 property:
@@ -47,7 +54,7 @@  RGMII1 RGMII2 RMII1 RMII2 SD1 SPI1 SPI1DEBUG SPI1PASSTHRU TIMER4 TIMER5 TIMER6
 TIMER7 TIMER8 VGABIOSROM
 
 
-Examples:
+g4 Example:
 
 syscon: scu@1e6e2000 {
 	compatible = "syscon", "simple-mfd";
@@ -63,5 +70,34 @@  syscon: scu@1e6e2000 {
 	};
 };
 
+g5 Example:
+
+apb {
+	gfx: display@1e6e6000 {
+		compatible = "aspeed,ast2500-gfx", "syscon";
+		reg = <0x1e6e6000 0x1000>;
+	};
+
+	lpchc: lpchc@1e7890a0 {
+		compatible = "aspeed,ast2500-lpchc", "syscon";
+		reg = <0x1e7890a0 0xc4>;
+	};
+
+	syscon: scu@1e6e2000 {
+		compatible = "syscon", "simple-mfd";
+		reg = <0x1e6e2000 0x1a8>;
+
+		pinctrl: pinctrl {
+			compatible = "aspeed,g5-pinctrl";
+			aspeed,external-nodes = <&gfx, &lpchc>;
+
+			pinctrl_i2c3_default: i2c3_default {
+				function = "I2C3";
+				groups = "I2C3";
+			};
+		};
+	};
+};
+
 Please refer to pinctrl-bindings.txt in this directory for details of the
 common pinctrl bindings used by client devices.
diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c b/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c
index a21b071ff290..558bd102416c 100644
--- a/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed-g4.c
@@ -292,7 +292,7 @@  SSSF_PIN_DECL(U18, GPIOG7, FLWP, SIG_DESC_SET(SCU84, 7));
 #define UART6_DESC	SIG_DESC_SET(SCU90, 7)
 #define ROM16_DESC	SIG_DESC_SET(SCU90, 6)
 #define FLASH_WIDE	SIG_DESC_SET(HW_STRAP1, 4)
-#define BOOT_SRC_NOR	{ HW_STRAP1, GENMASK(1, 0), 0, 0 }
+#define BOOT_SRC_NOR	{ ASPEED_IP_SCU, HW_STRAP1, GENMASK(1, 0), 0, 0 }
 
 #define A8 56
 SIG_EXPR_DECL(ROMD8, ROM16, ROM16_DESC);
@@ -418,9 +418,9 @@  FUNC_GROUP_DECL(I2C8, G5, F3);
 #define U1 88
 SSSF_PIN_DECL(U1, GPIOL0, NCTS1, SIG_DESC_SET(SCU84, 16));
 
-#define VPI18_DESC	{ SCU90, GENMASK(5, 4), 1, 0 }
-#define VPI24_DESC	{ SCU90, GENMASK(5, 4), 2, 0 }
-#define VPI30_DESC	{ SCU90, GENMASK(5, 4), 3, 0 }
+#define VPI18_DESC	{ ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 1, 0 }
+#define VPI24_DESC	{ ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 2, 0 }
+#define VPI30_DESC	{ ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 3, 0 }
 
 #define T5 89
 #define T5_DESC         SIG_DESC_SET(SCU84, 17)
@@ -641,11 +641,11 @@  SSSF_PIN_DECL(Y22, GPIOR2, ROMCS3, SIG_DESC_SET(SCU88, 26));
 #define U19 139
 SSSF_PIN_DECL(U19, GPIOR3, ROMCS4, SIG_DESC_SET(SCU88, 27));
 
-#define VPOOFF0_DESC	{ SCU94, GENMASK(1, 0), 0, 0 }
-#define VPO12_DESC	{ SCU94, GENMASK(1, 0), 1, 0 }
-#define VPO24_DESC	{ SCU94, GENMASK(1, 0), 2, 0 }
-#define VPOOFF1_DESC	{ SCU94, GENMASK(1, 0), 3, 0 }
-#define VPO_OFF_12      { SCU94, 0x2, 0, 0 }
+#define VPOOFF0_DESC	{ ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 0, 0 }
+#define VPO12_DESC	{ ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 1, 0 }
+#define VPO24_DESC	{ ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 2, 0 }
+#define VPOOFF1_DESC	{ ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 3, 0 }
+#define VPO_OFF_12      { ASPEED_IP_SCU, SCU94, 0x2, 0, 0 }
 #define VPO_24_OFF      SIG_DESC_SET(SCU94, 1)
 
 #define V21 140
diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c b/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c
index 87b46390b695..c5c9a1b6fa1c 100644
--- a/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed-g5.c
@@ -10,6 +10,7 @@ 
 #include <linux/init.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/mfd/syscon.h>
 #include <linux/mutex.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
@@ -26,8 +27,8 @@ 
 
 #define ASPEED_G5_NR_PINS 228
 
-#define COND1		{ SCU90, BIT(6), 0, 0 }
-#define COND2		{ SCU94, GENMASK(1, 0), 0, 0 }
+#define COND1		{ ASPEED_IP_SCU, SCU90, BIT(6), 0, 0 }
+#define COND2		{ ASPEED_IP_SCU, SCU94, GENMASK(1, 0), 0, 0 }
 
 #define B14 0
 SSSF_PIN_DECL(B14, GPIOA0, MAC1LINK, SIG_DESC_SET(SCU80, 0));
@@ -186,9 +187,12 @@  MS_PIN_DECL(C20, GPIOE1, NDCD3, GPIE0OUT);
 
 FUNC_GROUP_DECL(GPIE0, B20, C20);
 
-#define SPI1_DESC		{ HW_STRAP1, GENMASK(13, 12), 1, 0 }
-#define SPI1DEBUG_DESC		{ HW_STRAP1, GENMASK(13, 12), 2, 0 }
-#define SPI1PASSTHRU_DESC	{ HW_STRAP1, GENMASK(13, 12), 3, 0 }
+#define SPI1_DESC \
+	{ ASPEED_IP_SCU, HW_STRAP1, GENMASK(13, 12), 1, 0 }
+#define SPI1DEBUG_DESC \
+	{ ASPEED_IP_SCU, HW_STRAP1, GENMASK(13, 12), 2, 0 }
+#define SPI1PASSTHRU_DESC \
+	{ ASPEED_IP_SCU, HW_STRAP1, GENMASK(13, 12), 3, 0 }
 
 #define C18 64
 SIG_EXPR_DECL(SYSCS, SPI1DEBUG, COND1, SPI1DEBUG_DESC);
@@ -325,10 +329,11 @@  SS_PIN_DECL(R1, GPIOK7, SDA8);
 
 FUNC_GROUP_DECL(I2C8, P2, R1);
 
-#define VPIOFF0_DESC    { SCU90, GENMASK(5, 4), 0, 0 }
-#define VPIOFF1_DESC    { SCU90, GENMASK(5, 4), 1, 0 }
-#define VPI24_DESC      { SCU90, GENMASK(5, 4), 2, 0 }
-#define VPIRSVD_DESC    { SCU90, GENMASK(5, 4), 3, 0 }
+#define VPIOFF0_DESC    { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 0, 0 }
+#define VPIOFF1_DESC    { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 1, 0 }
+#define VPI24_DESC      { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 2, 0 }
+#define VPIRSVD_DESC    { ASPEED_IP_SCU, SCU90, GENMASK(5, 4), 3, 0 }
+
 
 #define V2 104
 #define V2_DESC         SIG_DESC_SET(SCU88, 0)
@@ -848,10 +853,35 @@  static struct pinctrl_desc aspeed_g5_pinctrl_desc = {
 static int aspeed_g5_pinctrl_probe(struct platform_device *pdev)
 {
 	int i;
+	struct regmap *map;
+	struct device_node *node;
 
 	for (i = 0; i < ARRAY_SIZE(aspeed_g5_pins); i++)
 		aspeed_g5_pins[i].number = i;
 
+	node = of_parse_phandle(pdev->dev.of_node, "aspeed,external-nodes", 0);
+	map = syscon_node_to_regmap(node);
+	of_node_put(node);
+	if (IS_ERR(map)) {
+		dev_warn(&pdev->dev, "No GFX phandle found, some mux configurations may fail\n");
+		map = NULL;
+	}
+	aspeed_g5_pinctrl_data.maps[ASPEED_IP_GFX] = map;
+
+	node = of_parse_phandle(pdev->dev.of_node, "aspeed,external-nodes", 1);
+	if (node) {
+		map = syscon_node_to_regmap(node->parent);
+		if (IS_ERR(map)) {
+			dev_warn(&pdev->dev, "LHC parent is not a syscon, some mux configurations may fail\n");
+			map = NULL;
+		}
+	} else {
+		dev_warn(&pdev->dev, "No LHC phandle found, some mux configurations may fail\n");
+		map = NULL;
+	}
+	of_node_put(node);
+	aspeed_g5_pinctrl_data.maps[ASPEED_IP_LPC] = map;
+
 	return aspeed_pinctrl_probe(pdev, &aspeed_g5_pinctrl_desc,
 			&aspeed_g5_pinctrl_data);
 }
diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.c b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
index 49aeba912531..782c5c97f853 100644
--- a/drivers/pinctrl/aspeed/pinctrl-aspeed.c
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.c
@@ -14,6 +14,12 @@ 
 #include "../core.h"
 #include "pinctrl-aspeed.h"
 
+static const char *const aspeed_pinmux_ips[] = {
+	[ASPEED_IP_SCU] = "SCU",
+	[ASPEED_IP_GFX] = "GFX",
+	[ASPEED_IP_LPC] = "LPC",
+};
+
 int aspeed_pinctrl_get_groups_count(struct pinctrl_dev *pctldev)
 {
 	struct aspeed_pinctrl_data *pdata = pinctrl_dev_get_drvdata(pctldev);
@@ -78,7 +84,8 @@  int aspeed_pinmux_get_fn_groups(struct pinctrl_dev *pctldev,
 static inline void aspeed_sig_desc_print_val(
 		const struct aspeed_sig_desc *desc, bool enable, u32 rv)
 {
-	pr_debug("SCU%x[0x%08x]=0x%x, got 0x%x from 0x%08x\n", desc->reg,
+	pr_debug("Want %s%X[0x%08X]=0x%X, got 0x%X from 0x%08X\n",
+			aspeed_pinmux_ips[desc->ip], desc->reg,
 			desc->mask, enable ? desc->enable : desc->disable,
 			(rv & desc->mask) >> __ffs(desc->mask), rv);
 }
@@ -88,10 +95,11 @@  static inline void aspeed_sig_desc_print_val(
  *
  * @desc: The signal descriptor of interest
  * @enabled: True to query the enabled state, false to query disabled state
- * @regmap: The SCU regmap instance
+ * @regmap: The IP block's regmap instance
  *
- * @return True if the descriptor's bitfield is configured to the state
- * selected by @enabled, false otherwise
+ * @return 1 if the descriptor's bitfield is configured to the state
+ * selected by @enabled, 0 if not, and less than zero if an unrecoverable
+ * failure occurred
  *
  * Evaluation of descriptor state is non-trivial in that it is not a binary
  * outcome: The bitfields can be greater than one bit in size and thus can take
@@ -99,14 +107,19 @@  static inline void aspeed_sig_desc_print_val(
  * descriptor (typically this means a different function to the one of interest
  * is enabled). Thus we must explicitly test for either condition as required.
  */
-static bool aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
+static int aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
 				 bool enabled, struct regmap *map)
 {
+	int ret;
 	unsigned int raw;
 	u32 want;
 
-	if (regmap_read(map, desc->reg, &raw) < 0)
-		return false;
+	if (!map)
+		return -ENODEV;
+
+	ret = regmap_read(map, desc->reg, &raw);
+	if (ret)
+		return ret;
 
 	aspeed_sig_desc_print_val(desc, enabled, raw);
 	want = enabled ? desc->enable : desc->disable;
@@ -119,10 +132,10 @@  static bool aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
  *
  * @expr: An expression controlling the signal for a mux function on a pin
  * @enabled: True to query the enabled state, false to query disabled state
- * @regmap: The SCU regmap instance
+ * @maps: The list of regmap instances
  *
- * @return True if the expression composed by @enabled evaluates true, false
- * otherwise
+ * @return 1 if the expression composed by @enabled evaluates true, 0 if not,
+ * and less than zero if an unrecoverable failure occurred.
  *
  * A mux function is enabled or disabled if the function's signal expression
  * for each pin in the function's pin group evaluates true for the desired
@@ -135,19 +148,21 @@  static bool aspeed_sig_desc_eval(const struct aspeed_sig_desc *desc,
  * neither the enabled nor disabled state. Thus we must explicitly test for
  * either condition as required.
  */
-static bool aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
-				 bool enabled, struct regmap *map)
+static int aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
+				 bool enabled, struct regmap * const *maps)
 {
 	int i;
+	int ret;
 
 	for (i = 0; i < expr->ndescs; i++) {
 		const struct aspeed_sig_desc *desc = &expr->descs[i];
 
-		if (!aspeed_sig_desc_eval(desc, enabled, map))
-			return false;
+		ret = aspeed_sig_desc_eval(desc, enabled, maps[desc->ip]);
+		if (ret <= 0)
+			return ret;
 	}
 
-	return true;
+	return 1;
 }
 
 /**
@@ -158,19 +173,24 @@  static bool aspeed_sig_expr_eval(const struct aspeed_sig_expr *expr,
  *        configured
  * @enable: true to enable an function's signal through a pin's signal
  *          expression, false to disable the function's signal
- * @map: The SCU's regmap instance for pinmux register access.
+ * @maps: The list of regmap instances for pinmux register access.
  *
- * @return true if the expression is configured as requested, false otherwise
+ * @return 0 if the expression is configured as requested and a negative error
+ * code otherwise
  */
-static bool aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
-				bool enable, struct regmap *map)
+static int aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
+				bool enable, struct regmap * const *maps)
 {
+	int ret;
 	int i;
 
 	for (i = 0; i < expr->ndescs; i++) {
-		bool ret;
 		const struct aspeed_sig_desc *desc = &expr->descs[i];
 		u32 pattern = enable ? desc->enable : desc->disable;
+		u32 val = (pattern << __ffs(desc->mask));
+
+		if (!maps[desc->ip])
+			return -ENODEV;
 
 		/*
 		 * Strap registers are configured in hardware or by early-boot
@@ -179,64 +199,79 @@  static bool aspeed_sig_expr_set(const struct aspeed_sig_expr *expr,
 		 * deconfigured and is the reason we re-evaluate after writing
 		 * all descriptor bits.
 		 */
-		if (desc->reg == HW_STRAP1 || desc->reg == HW_STRAP2)
+		if ((desc->reg == HW_STRAP1 || desc->reg == HW_STRAP2) &&
+				desc->ip == ASPEED_IP_SCU)
 			continue;
 
-		ret = regmap_update_bits(map, desc->reg, desc->mask,
-				pattern << __ffs(desc->mask)) == 0;
+		ret = regmap_update_bits(maps[desc->ip], desc->reg,
+					 desc->mask, val);
 
-		if (!ret)
+		if (ret)
 			return ret;
 	}
 
-	return aspeed_sig_expr_eval(expr, enable, map);
+	ret = aspeed_sig_expr_eval(expr, enable, maps);
+	if (ret < 0)
+		return ret;
+
+	if (!ret)
+		return -EPERM;
+
+	return 0;
 }
 
-static bool aspeed_sig_expr_enable(const struct aspeed_sig_expr *expr,
-				   struct regmap *map)
+static int aspeed_sig_expr_enable(const struct aspeed_sig_expr *expr,
+				   struct regmap * const *maps)
 {
-	if (aspeed_sig_expr_eval(expr, true, map))
-		return true;
+	int ret;
+
+	ret = aspeed_sig_expr_eval(expr, true, maps);
+	if (ret < 0)
+		return ret;
 
-	return aspeed_sig_expr_set(expr, true, map);
+	if (!ret)
+		return aspeed_sig_expr_set(expr, true, maps);
+
+	return 0;
 }
 
-static bool aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
-				    struct regmap *map)
+static int aspeed_sig_expr_disable(const struct aspeed_sig_expr *expr,
+				    struct regmap * const *maps)
 {
-	if (!aspeed_sig_expr_eval(expr, true, map))
-		return true;
+	int ret;
+
+	ret = aspeed_sig_expr_eval(expr, true, maps);
+	if (ret < 0)
+		return ret;
+
+	if (ret)
+		return aspeed_sig_expr_set(expr, false, maps);
 
-	return aspeed_sig_expr_set(expr, false, map);
+	return 0;
 }
 
 /**
  * Disable a signal on a pin by disabling all provided signal expressions.
  *
  * @exprs: The list of signal expressions (from a priority level on a pin)
- * @map: The SCU's regmap instance for pinmux register access.
+ * @maps: The list of regmap instances for pinmux register access.
  *
- * @return true if all expressions in the list are successfully disabled, false
- * otherwise
+ * @return 0 if all expressions are disabled, otherwise a negative error code
  */
-static bool aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
-			       struct regmap *map)
+static int aspeed_disable_sig(const struct aspeed_sig_expr **exprs,
+			       struct regmap * const *maps)
 {
-	bool disabled = true;
+	int ret = 0;
 
 	if (!exprs)
 		return true;
 
-	while (*exprs) {
-		bool ret;
-
-		ret = aspeed_sig_expr_disable(*exprs, map);
-		disabled = disabled && ret;
-
+	while (*exprs && !ret) {
+		ret = aspeed_sig_expr_disable(*exprs, maps);
 		exprs++;
 	}
 
-	return disabled;
+	return ret;
 }
 
 /**
@@ -330,6 +365,7 @@  int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 			  unsigned int group)
 {
 	int i;
+	int ret;
 	const struct aspeed_pinctrl_data *pdata =
 		pinctrl_dev_get_drvdata(pctldev);
 	const struct aspeed_pin_group *pgroup = &pdata->groups[group];
@@ -343,6 +379,8 @@  int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 		const struct aspeed_sig_expr **funcs;
 		const struct aspeed_sig_expr ***prios;
 
+		pr_debug("Muxing pin %d for %s\n", pin, pfunc->name);
+
 		if (!pdesc)
 			return -EINVAL;
 
@@ -358,8 +396,9 @@  int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 			if (expr)
 				break;
 
-			if (!aspeed_disable_sig(funcs, pdata->map))
-				return -EPERM;
+			ret = aspeed_disable_sig(funcs, pdata->maps);
+			if (ret)
+				return ret;
 
 			prios++;
 		}
@@ -377,8 +416,9 @@  int aspeed_pinmux_set_mux(struct pinctrl_dev *pctldev, unsigned int function,
 			return -ENXIO;
 		}
 
-		if (!aspeed_sig_expr_enable(expr, pdata->map))
-			return -EPERM;
+		ret = aspeed_sig_expr_enable(expr, pdata->maps);
+		if (ret)
+			return ret;
 	}
 
 	return 0;
@@ -414,6 +454,7 @@  int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
 			       struct pinctrl_gpio_range *range,
 			       unsigned int offset)
 {
+	int ret;
 	const struct aspeed_pinctrl_data *pdata =
 		pinctrl_dev_get_drvdata(pctldev);
 	const struct aspeed_pin_desc *pdesc = pdata->pins[offset].drv_data;
@@ -432,8 +473,9 @@  int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
 		if (aspeed_gpio_in_exprs(funcs))
 			break;
 
-		if (!aspeed_disable_sig(funcs, pdata->map))
-			return -EPERM;
+		ret = aspeed_disable_sig(funcs, pdata->maps);
+		if (ret)
+			return ret;
 
 		prios++;
 	}
@@ -462,10 +504,7 @@  int aspeed_gpio_request_enable(struct pinctrl_dev *pctldev,
 	 * If GPIO is not the lowest priority signal type, assume there is only
 	 * one expression defined to enable the GPIO function
 	 */
-	if (!aspeed_sig_expr_enable(expr, pdata->map))
-		return -EPERM;
-
-	return 0;
+	return aspeed_sig_expr_enable(expr, pdata->maps);
 }
 
 int aspeed_pinctrl_probe(struct platform_device *pdev,
@@ -481,10 +520,10 @@  int aspeed_pinctrl_probe(struct platform_device *pdev,
 		return -ENODEV;
 	}
 
-	pdata->map = syscon_node_to_regmap(parent->of_node);
-	if (IS_ERR(pdata->map)) {
+	pdata->maps[ASPEED_IP_SCU] = syscon_node_to_regmap(parent->of_node);
+	if (IS_ERR(pdata->maps[ASPEED_IP_SCU])) {
 		dev_err(&pdev->dev, "No regmap for syscon pincontroller parent\n");
-		return PTR_ERR(pdata->map);
+		return PTR_ERR(pdata->maps[ASPEED_IP_SCU]);
 	}
 
 	pctl = pinctrl_register(pdesc, &pdev->dev, pdata);
diff --git a/drivers/pinctrl/aspeed/pinctrl-aspeed.h b/drivers/pinctrl/aspeed/pinctrl-aspeed.h
index 3e72ef8c54bf..0e93cbf2ff33 100644
--- a/drivers/pinctrl/aspeed/pinctrl-aspeed.h
+++ b/drivers/pinctrl/aspeed/pinctrl-aspeed.h
@@ -232,6 +232,11 @@ 
  * group.
  */
 
+#define ASPEED_IP_SCU		0
+#define ASPEED_IP_GFX		1
+#define ASPEED_IP_LPC		2
+#define ASPEED_NR_PINMUX_IPS	3
+
 /*
  * The "Multi-function Pins Mapping and Control" table in the SoC datasheet
  * references registers by the device/offset mnemonic. The register macros
@@ -261,7 +266,9 @@ 
   * A signal descriptor, which describes the register, bits and the
   * enable/disable values that should be compared or written.
   *
-  * @reg: The register offset from base in bytes
+  * @ip: The IP block identifier, used as an index into the regmap array in
+  *      struct aspeed_pinctrl_data
+  * @reg: The register offset with respect to the base address of the IP block
   * @mask: The mask to apply to the register. The lowest set bit of the mask is
   *        used to derive the shift value.
   * @enable: The value that enables the function. Value should be in the LSBs,
@@ -270,6 +277,7 @@ 
   *           LSBs, not at the position of the mask.
   */
 struct aspeed_sig_desc {
+	unsigned int ip;
 	unsigned int reg;
 	u32 mask;
 	u32 enable;
@@ -313,24 +321,30 @@  struct aspeed_pin_desc {
 
 /* Macro hell */
 
+#define SIG_DESC_IP_BIT(ip, reg, idx, val) \
+	{ ip, reg, BIT_MASK(idx), val, (((val) + 1) & 1) }
+
 /**
- * Short-hand macro for describing a configuration enabled by the state of one
- * bit. The disable value is derived.
+ * Short-hand macro for describing an SCU descriptor enabled by the state of
+ * one bit. The disable value is derived.
  *
  * @reg: The signal's associated register, offset from base
  * @idx: The signal's bit index in the register
  * @val: The value (0 or 1) that enables the function
  */
 #define SIG_DESC_BIT(reg, idx, val) \
-	{ reg, BIT_MASK(idx), val, (((val) + 1) & 1) }
+	SIG_DESC_IP_BIT(ASPEED_IP_SCU, reg, idx, val)
+
+#define SIG_DESC_IP_SET(ip, reg, idx) SIG_DESC_IP_BIT(ip, reg, idx, 1)
 
 /**
- * A further short-hand macro describing a configuration enabled with a set bit.
+ * A further short-hand macro expanding to an SCU descriptor enabled by a set
+ * bit.
  *
- * @reg: The configuration's associated register, offset from base
- * @idx: The configuration's bit index in the register
+ * @reg: The register, offset from base
+ * @idx: The bit index in the register
  */
-#define SIG_DESC_SET(reg, idx) SIG_DESC_BIT(reg, idx, 1)
+#define SIG_DESC_SET(reg, idx) SIG_DESC_IP_BIT(ASPEED_IP_SCU, reg, idx, 1)
 
 #define SIG_DESC_LIST_SYM(sig, func) sig_descs_ ## sig ## _ ## func
 #define SIG_DESC_LIST_DECL(sig, func, ...) \
@@ -500,7 +514,7 @@  struct aspeed_pin_desc {
 	MS_PIN_DECL_(pin, SIG_EXPR_LIST_PTR(gpio))
 
 struct aspeed_pinctrl_data {
-	struct regmap *map;
+	struct regmap *maps[ASPEED_NR_PINMUX_IPS];
 
 	const struct pinctrl_pin_desc *pins;
 	const unsigned int npins;