Message ID | 1434024020-17048-3-git-send-email-cuissard@marvell.com |
---|---|
State | Accepted, archived |
Headers | show |
Adding Neil Brown who has been doing a UART slave binding[1]. On Thu, Jun 11, 2015 at 7:00 AM, Vincent Cuissard <cuissard@marvell.com> wrote: > Add support of Marvell NFC chip controlled over UART > > Signed-off-by: Vincent Cuissard <cuissard@marvell.com> > --- > .../devicetree/bindings/net/nfc/nfcmrvl.txt | 29 +++ > drivers/nfc/nfcmrvl/Kconfig | 11 + > drivers/nfc/nfcmrvl/Makefile | 3 + > drivers/nfc/nfcmrvl/nfcmrvl.h | 7 + > drivers/nfc/nfcmrvl/uart.c | 225 +++++++++++++++++++++ > include/linux/platform_data/nfcmrvl.h | 9 + > net/nfc/nci/uart.c | 1 - > 7 files changed, 284 insertions(+), 1 deletion(-) > create mode 100644 Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt > create mode 100644 drivers/nfc/nfcmrvl/uart.c > > diff --git a/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt b/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt > new file mode 100644 > index 0000000..7c4a0cc > --- /dev/null > +++ b/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt > @@ -0,0 +1,29 @@ > +* Marvell International Ltd. NCI NFC Controller > + > +Required properties: > +- compatible: Should be "mrvl,nfc-uart". This should describe the chip, not the connection. marvell is the preferred vendor prefix. mrvl is deprecated. > +Optional SoC specific properties: > +- pinctrl-names: Contains only one value - "default". > +- pintctrl-0: Specifies the pin control groups used for this controller. What pins are you controlling exactly? The UART signals on the host? > +- reset-n-io: Output GPIO pin used to reset the chip (active low). Should be suffixed with "-gpio". Is this reset for the chip or only NFC? > +- hci-muxed: Specifies that the chip is muxing NCI over HCI frames. > + > +Optional UART-based chip specific properties: > +- flow-control: Specifies that the chip is using RTS/CTS. Is this a setting in the NFC chip or just how the UART is configured. If the latter, we already have standard UART property to enable flow-control on a UART. > +- break-control: Specifies that the chip needs specific break management. Can you be more specific? > + > +Example (for ARM-based BeagleBoard Black with 88W8887 on UART5): > + > +&uart5 { > + status = "okay"; > + > + nfcmrvluart: nfcmrvluart@5 { Unit addresses should have a corresponding reg property. You don't need a reg property here, so drop the unit address. Names should allow be generic, so just "nfc" is probably sufficient here. Or maybe "uart-slave". How are you doing the binding for the rest of the 8887 chip which has also has BT and WiFi. We need to figure out how to do the whole chip which is a bit more complicated, but quite common. We could split up each function, but then I worry that there may be some interdependencies between functions on the chip. > + compatible = "mrvl,nfc-uart"; > + > + reset-n-io = <&gpio3 16 0>; > + > + hci-muxed; > + flow-control; > + } > +}; Rob [1] https://lwn.net/Articles/643878/ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, 11 Jun 2015 23:06:54 -0500 Rob Herring <robherring2@gmail.com> wrote: > Adding Neil Brown who has been doing a UART slave binding[1]. Thanks for the heads-up. This is quite a different approach to configuring a device that is attached to a UART, but then I think it is trying to handle different issues than my approach and the two can easily co-exist. My need was for a driver to be activated when the tty device was opened. So the uart needs to examine the child in devicetree, find the "compatible" driver, probe it, and allow it to intercept "open" requests. This need is to be able to configure a particular driver that is attached to a particular line discipline. So (if I understand correctly), the /dev/ttyXX would be opened, an line discipline would be selected, and ioctl to that line discipline would select the driver and then that drive goes and looks in devicetree, find the configuration, and makes use of it. It may be a pipe dream, but it might be nice if these could be combined. When the uart looks in device tree, if it finds a child which specifies a line-discipline, it could activate that line discipline directly which could then extract other information and activate the relevant drive, which could then gather the relevant configuration information. I do think my current code would get confused if it found this device tree node under a uart. It currently thinks any device tree node with a "compatible" attribute implies a device that will have a driver. So it won't register the tty device until that driver appears. That would be a problem for this NFC driver. It probably makes sense to change my approach so that the tty still gets registered immediately, but when the driver appears it gets connected in to the tty somehow. I'll have to give that some thought. Thanks, NeilBrown > > On Thu, Jun 11, 2015 at 7:00 AM, Vincent Cuissard <cuissard@marvell.com> wrote: > > Add support of Marvell NFC chip controlled over UART > > > > Signed-off-by: Vincent Cuissard <cuissard@marvell.com> > > --- > > .../devicetree/bindings/net/nfc/nfcmrvl.txt | 29 +++ > > drivers/nfc/nfcmrvl/Kconfig | 11 + > > drivers/nfc/nfcmrvl/Makefile | 3 + > > drivers/nfc/nfcmrvl/nfcmrvl.h | 7 + > > drivers/nfc/nfcmrvl/uart.c | 225 +++++++++++++++++++++ > > include/linux/platform_data/nfcmrvl.h | 9 + > > net/nfc/nci/uart.c | 1 - > > 7 files changed, 284 insertions(+), 1 deletion(-) > > create mode 100644 Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt > > create mode 100644 drivers/nfc/nfcmrvl/uart.c > > > > diff --git a/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt b/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt > > new file mode 100644 > > index 0000000..7c4a0cc > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt > > @@ -0,0 +1,29 @@ > > +* Marvell International Ltd. NCI NFC Controller > > + > > +Required properties: > > +- compatible: Should be "mrvl,nfc-uart". > > This should describe the chip, not the connection. > > marvell is the preferred vendor prefix. mrvl is deprecated. > > > > +Optional SoC specific properties: > > +- pinctrl-names: Contains only one value - "default". > > +- pintctrl-0: Specifies the pin control groups used for this controller. > > What pins are you controlling exactly? The UART signals on the host? > > > +- reset-n-io: Output GPIO pin used to reset the chip (active low). > > Should be suffixed with "-gpio". Is this reset for the chip or only NFC? > > > +- hci-muxed: Specifies that the chip is muxing NCI over HCI frames. > > + > > +Optional UART-based chip specific properties: > > +- flow-control: Specifies that the chip is using RTS/CTS. > > Is this a setting in the NFC chip or just how the UART is configured. > If the latter, we already have standard UART property to enable > flow-control on a UART. > > > +- break-control: Specifies that the chip needs specific break management. > > Can you be more specific? > > > + > > +Example (for ARM-based BeagleBoard Black with 88W8887 on UART5): > > + > > +&uart5 { > > + status = "okay"; > > + > > + nfcmrvluart: nfcmrvluart@5 { > > Unit addresses should have a corresponding reg property. You don't > need a reg property here, so drop the unit address. Names should allow > be generic, so just "nfc" is probably sufficient here. Or maybe > "uart-slave". > > How are you doing the binding for the rest of the 8887 chip which has > also has BT and WiFi. We need to figure out how to do the whole chip > which is a bit more complicated, but quite common. We could split up > each function, but then I worry that there may be some > interdependencies between functions on the chip. > > > + compatible = "mrvl,nfc-uart"; > > + > > + reset-n-io = <&gpio3 16 0>; > > + > > + hci-muxed; > > + flow-control; > > + } > > +}; > > Rob > > [1] https://lwn.net/Articles/643878/ -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt b/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt new file mode 100644 index 0000000..7c4a0cc --- /dev/null +++ b/Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt @@ -0,0 +1,29 @@ +* Marvell International Ltd. NCI NFC Controller + +Required properties: +- compatible: Should be "mrvl,nfc-uart". + +Optional SoC specific properties: +- pinctrl-names: Contains only one value - "default". +- pintctrl-0: Specifies the pin control groups used for this controller. +- reset-n-io: Output GPIO pin used to reset the chip (active low). +- hci-muxed: Specifies that the chip is muxing NCI over HCI frames. + +Optional UART-based chip specific properties: +- flow-control: Specifies that the chip is using RTS/CTS. +- break-control: Specifies that the chip needs specific break management. + +Example (for ARM-based BeagleBoard Black with 88W8887 on UART5): + +&uart5 { + status = "okay"; + + nfcmrvluart: nfcmrvluart@5 { + compatible = "mrvl,nfc-uart"; + + reset-n-io = <&gpio3 16 0>; + + hci-muxed; + flow-control; + } +}; diff --git a/drivers/nfc/nfcmrvl/Kconfig b/drivers/nfc/nfcmrvl/Kconfig index 5e18afd..796be24 100644 --- a/drivers/nfc/nfcmrvl/Kconfig +++ b/drivers/nfc/nfcmrvl/Kconfig @@ -21,3 +21,14 @@ config NFC_MRVL_USB Say Y here to compile support for Marvell NFC-over-USB driver into the kernel or say M to compile it as module. + +config NFC_MRVL_UART + tristate "Marvell NFC-over-UART driver" + depends on NFC_MRVL && NFC_NCI_UART + help + Marvell NFC-over-UART driver. + + This driver provides support for Marvell NFC-over-UART devices + + Say Y here to compile support for Marvell NFC-over-UART driver + into the kernel or say M to compile it as module. diff --git a/drivers/nfc/nfcmrvl/Makefile b/drivers/nfc/nfcmrvl/Makefile index 97a0de7..7751962 100644 --- a/drivers/nfc/nfcmrvl/Makefile +++ b/drivers/nfc/nfcmrvl/Makefile @@ -7,3 +7,6 @@ obj-$(CONFIG_NFC_MRVL) += nfcmrvl.o nfcmrvl_usb-y += usb.o obj-$(CONFIG_NFC_MRVL_USB) += nfcmrvl_usb.o + +nfcmrvl_uart-y += uart.o +obj-$(CONFIG_NFC_MRVL_UART) += nfcmrvl_uart.o diff --git a/drivers/nfc/nfcmrvl/nfcmrvl.h b/drivers/nfc/nfcmrvl/nfcmrvl.h index 214412b..09780d5 100644 --- a/drivers/nfc/nfcmrvl/nfcmrvl.h +++ b/drivers/nfc/nfcmrvl/nfcmrvl.h @@ -43,6 +43,11 @@ #define NFCMRVL_HCI_OGF 0x81 #define NFCMRVL_HCI_OCF 0xFE +enum nfcmrvl_phy { + NFCMRVL_PHY_USB = 0, + NFCMRVL_PHY_UART = 1, +}; + struct nfcmrvl_private { @@ -61,6 +66,8 @@ struct nfcmrvl_private { void *drv_data; /* PHY device */ struct device *dev; + /* PHY type */ + enum nfcmrvl_phy phy; /* Low level driver ops */ struct nfcmrvl_if_ops *if_ops; }; diff --git a/drivers/nfc/nfcmrvl/uart.c b/drivers/nfc/nfcmrvl/uart.c new file mode 100644 index 0000000..61442d6 --- /dev/null +++ b/drivers/nfc/nfcmrvl/uart.c @@ -0,0 +1,225 @@ +/** + * Marvell NFC-over-UART driver + * + * Copyright (C) 2015, Marvell International Ltd. + * + * This software file (the "File") is distributed by Marvell International + * Ltd. under the terms of the GNU General Public License Version 2, June 1991 + * (the "License"). You may use, redistribute and/or modify this File in + * accordance with the terms and conditions of the License, a copy of which + * is available on the worldwide web at + * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt. + * + * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE + * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE + * ARE EXPRESSLY DISCLAIMED. The License provides additional details about + * this warranty disclaimer. + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/of_gpio.h> +#include <net/nfc/nci.h> +#include <net/nfc/nci_core.h> +#include "nfcmrvl.h" + +static unsigned int hci_muxed; +static unsigned int flow_control; +static unsigned int break_control; +static unsigned int reset_n_io; + +/* +** NFCMRVL NCI OPS +*/ + +static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv) +{ + return 0; +} + +static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv) +{ + return 0; +} + +static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv, + struct sk_buff *skb) +{ + struct nci_uart *nu = priv->drv_data; + + return nu->ops.send(nu, skb); +} + +static struct nfcmrvl_if_ops uart_ops = { + .nci_open = nfcmrvl_uart_nci_open, + .nci_close = nfcmrvl_uart_nci_close, + .nci_send = nfcmrvl_uart_nci_send, +}; + +#ifdef CONFIG_OF + +static int nfcmrvl_uart_parse_dt(struct device_node *node, + struct nfcmrvl_platform_data *pdata) +{ + struct device_node *matched_node; + int ret; + + matched_node = of_find_compatible_node(node, NULL, "mrvl,nfc-uart"); + if (!matched_node) + return -ENODEV; + + ret = nfcmrvl_parse_dt(matched_node, pdata); + if (ret < 0) { + pr_err("Failed to get generic entries\n"); + return ret; + } + + if (of_find_property(matched_node, "flow-control", NULL)) + pdata->flow_control = 1; + else + pdata->flow_control = 0; + + if (of_find_property(matched_node, "break-control", NULL)) + pdata->break_control = 1; + else + pdata->break_control = 0; + + return 0; +} + +#else + +static int nfcmrvl_uart_parse_dt(struct device_node *node, + struct nfcmrvl_platform_data *pdata) +{ + return -ENODEV; +} + +#endif + +/* +** NCI UART OPS +*/ + +static int nfcmrvl_nci_uart_open(struct nci_uart *nu) +{ + struct nfcmrvl_private *priv; + struct nfcmrvl_platform_data *pdata = NULL; + struct nfcmrvl_platform_data config; + + /* + * Platform data cannot be used here since usually it is already used + * by low level serial driver. We can try to retrieve serial device + * and check if DT entries were added. + */ + + if (nu->tty->dev->parent && nu->tty->dev->parent->of_node) + if (nfcmrvl_uart_parse_dt(nu->tty->dev->parent->of_node, + &config) == 0) + pdata = &config; + + if (!pdata) { + pr_info("No platform data / DT -> fallback to module params\n"); + config.hci_muxed = hci_muxed; + config.reset_n_io = reset_n_io; + config.flow_control = flow_control; + config.break_control = break_control; + pdata = &config; + } + + priv = nfcmrvl_nci_register_dev(nu, &uart_ops, nu->tty->dev, pdata); + if (IS_ERR(priv)) + return PTR_ERR(priv); + + priv->phy = NFCMRVL_PHY_UART; + + nu->drv_data = priv; + nu->ndev = priv->ndev; + + /* Set BREAK */ + if (priv->config.break_control && nu->tty->ops->break_ctl) + nu->tty->ops->break_ctl(nu->tty, -1); + + return 0; +} + +static void nfcmrvl_nci_uart_close(struct nci_uart *nu) +{ + nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); +} + +static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) +{ + return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, + skb); +} + +static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) +{ + struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; + + /* Remove BREAK to wake up the NFCC */ + if (priv->config.break_control && nu->tty->ops->break_ctl) { + nu->tty->ops->break_ctl(nu->tty, 0); + usleep_range(3000, 5000); + } +} + +static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) +{ + struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; + + /* + ** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him + ** up. we set BREAK. Once we will be ready to send again we will remove + ** it. + */ + if (priv->config.break_control && nu->tty->ops->break_ctl) + nu->tty->ops->break_ctl(nu->tty, -1); +} + +static struct nci_uart nfcmrvl_nci_uart = { + .owner = THIS_MODULE, + .name = "nfcmrvl_uart", + .driver = NCI_UART_DRIVER_MARVELL, + .ops = { + .open = nfcmrvl_nci_uart_open, + .close = nfcmrvl_nci_uart_close, + .recv = nfcmrvl_nci_uart_recv, + .tx_start = nfcmrvl_nci_uart_tx_start, + .tx_done = nfcmrvl_nci_uart_tx_done, + } +}; + +/* +** Module init +*/ + +static int nfcmrvl_uart_init_module(void) +{ + return nci_uart_register(&nfcmrvl_nci_uart); +} + +static void nfcmrvl_uart_exit_module(void) +{ + nci_uart_unregister(&nfcmrvl_nci_uart); +} + +module_init(nfcmrvl_uart_init_module); +module_exit(nfcmrvl_uart_exit_module); + +MODULE_AUTHOR("Marvell International Ltd."); +MODULE_DESCRIPTION("Marvell NFC-over-UART"); +MODULE_LICENSE("GPL v2"); + +module_param(flow_control, uint, 0); +MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); + +module_param(break_control, uint, 0); +MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); + +module_param(hci_muxed, uint, 0); +MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); + +module_param(reset_n_io, uint, 0); +MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); diff --git a/include/linux/platform_data/nfcmrvl.h b/include/linux/platform_data/nfcmrvl.h index 106cfe5..ac91707 100644 --- a/include/linux/platform_data/nfcmrvl.h +++ b/include/linux/platform_data/nfcmrvl.h @@ -26,6 +26,15 @@ struct nfcmrvl_platform_data { unsigned int reset_n_io; /* Tell if transport is muxed in HCI one */ unsigned int hci_muxed; + + /* + * UART specific + */ + + /* Tell if UART needs flow control at init */ + unsigned int flow_control; + /* Tell if firmware supports break control for power management */ + unsigned int break_control; }; #endif /* _NFCMRVL_PTF_H_ */ diff --git a/net/nfc/nci/uart.c b/net/nfc/nci/uart.c index bd96f97..3592b3d 100644 --- a/net/nfc/nci/uart.c +++ b/net/nfc/nci/uart.c @@ -12,7 +12,6 @@ * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE * ARE EXPRESSLY DISCLAIMED. The License provides additional details about * this warranty disclaimer. - */ /*
Add support of Marvell NFC chip controlled over UART Signed-off-by: Vincent Cuissard <cuissard@marvell.com> --- .../devicetree/bindings/net/nfc/nfcmrvl.txt | 29 +++ drivers/nfc/nfcmrvl/Kconfig | 11 + drivers/nfc/nfcmrvl/Makefile | 3 + drivers/nfc/nfcmrvl/nfcmrvl.h | 7 + drivers/nfc/nfcmrvl/uart.c | 225 +++++++++++++++++++++ include/linux/platform_data/nfcmrvl.h | 9 + net/nfc/nci/uart.c | 1 - 7 files changed, 284 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/net/nfc/nfcmrvl.txt create mode 100644 drivers/nfc/nfcmrvl/uart.c