[v4,1/4] Power: Reset: Generalize qnap-poweroff to with on Synology devices.

From: Andrew Lunn <andrew@lunn.ch>

The Synology NAS devices use a very similar mechanism to QNAP NAS
devices to power off. Both send a single charactor command to a PIC,
over the second serial port. However the baud rate and the command
differ. Generalize the driver to support this.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Cc: Anton Vorontsov <anton@enomsg.org>
Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
---
 .../bindings/power_supply/qnap-poweroff.txt        |  5 ++-
 drivers/power/reset/qnap-poweroff.c                | 46 +++++++++++++++++-----
 2 files changed, 40 insertions(+), 11 deletions(-)

Hello-

Few nits below.

On Tue, Feb 18, 2014 at 07:45:34AM +1000, klightspeed@killerwolves.net wrote:
> From: Andrew Lunn <andrew@lunn.ch>
> 
> The Synology NAS devices use a very similar mechanism to QNAP NAS
> devices to power off. Both send a single charactor command to a PIC,
> over the second serial port. However the baud rate and the command
> differ. Generalize the driver to support this.
> 
> Signed-off-by: Andrew Lunn <andrew@lunn.ch>
> Acked-by: Jason Cooper <jason@lakedaemon.net>
> Cc: Anton Vorontsov <anton@enomsg.org>
> Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> Cc: David Woodhouse <dwmw2@infradead.org>
> ---
>  .../bindings/power_supply/qnap-poweroff.txt        |  5 ++-
>  drivers/power/reset/qnap-poweroff.c                | 46 +++++++++++++++++-----
>  2 files changed, 40 insertions(+), 11 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt b/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt
> index 0347d83..af25e77 100644
> --- a/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt
> +++ b/Documentation/devicetree/bindings/power_supply/qnap-poweroff.txt
> @@ -6,8 +6,11 @@ Orion5x SoCs. Sending the character 'A', at 19200 baud, tells the
>  microcontroller to turn the power off. This driver adds a handler to
>  pm_power_off which is called to turn the power off.
>  
> +Synology NAS devices use a similar scheme, but a different baud rate,
> +9600, and a different character, '1'.
> +
>  Required Properties:
> -- compatible: Should be "qnap,power-off"
> +- compatible: Should be "qnap,power-off" or "synology,power-off"

Hmm.. Neither 'qnap' or 'synology' are described in
Documentation/devicetree/bindings/vendor-prefixes.txt.  Perhaps they
should be added?

>  
>  - reg: Address and length of the register set for UART1
>  - clocks: tclk clock
> diff --git a/drivers/power/reset/qnap-poweroff.c b/drivers/power/reset/qnap-poweroff.c
> index 37f56f7..10c91fa 100644
> --- a/drivers/power/reset/qnap-poweroff.c
> +++ b/drivers/power/reset/qnap-poweroff.c
> @@ -1,5 +1,5 @@
>  /*
> - * QNAP Turbo NAS Board power off
> + * QNAP Turbo NAS Board power off. Can also be used on Synology devices.
>   *
>   * Copyright (C) 2012 Andrew Lunn <andrew@lunn.ch>
>   *
> @@ -25,17 +25,42 @@
>  
>  #define UART1_REG(x)	(base + ((UART_##x) << 2))
>  
> +struct power_off_cfg {
> +	u32 baud;
> +	char cmd;
> +};
> +
> +static const struct power_off_cfg qnap_power_off_cfg = {
> +	.baud = 19200,
> +	.cmd = 'A',
> +};
> +
> +static const struct power_off_cfg synology_power_off_cfg = {
> +	.baud = 9600,
> +	.cmd = '1',
> +};
> +
> +static const struct of_device_id qnap_power_off_of_match_table[] = {
> +	{ .compatible = "qnap,power-off",
> +	  .data = (void *) &qnap_power_off_cfg,
> +	},
> +	{ .compatible = "synology,power-off",
> +	  .data = (void *) &synology_power_off_cfg,

The casts here should not be necessary.

> +	},
> +	{}
> +};
> +
>  static void __iomem *base;
>  static unsigned long tclk;
> +static struct power_off_cfg *cfg;

const?

>  
>  static void qnap_power_off(void)
>  {
> -	/* 19200 baud divisor */
> -	const unsigned divisor = ((tclk + (8 * 19200)) / (16 * 19200));
> +	const unsigned divisor = ((tclk + (8 * cfg->baud)) / (16 * cfg->baud));
>  
>  	pr_err("%s: triggering power-off...\n", __func__);
>  
> -	/* hijack UART1 and reset into sane state (19200,8n1) */
> +	/* hijack UART1 and reset into sane state */
>  	writel(0x83, UART1_REG(LCR));
>  	writel(divisor & 0xff, UART1_REG(DLL));
>  	writel((divisor >> 8) & 0xff, UART1_REG(DLM));
> @@ -44,16 +69,21 @@ static void qnap_power_off(void)
>  	writel(0x00, UART1_REG(FCR));
>  	writel(0x00, UART1_REG(MCR));
>  
> -	/* send the power-off command 'A' to PIC */
> -	writel('A', UART1_REG(TX));
> +	/* send the power-off command to PIC */
> +	writel(cfg->cmd, UART1_REG(TX));
>  }
>  
>  static int qnap_power_off_probe(struct platform_device *pdev)
>  {
> +	struct device_node *np = pdev->dev.of_node;
>  	struct resource *res;
>  	struct clk *clk;
>  	char symname[KSYM_NAME_LEN];
>  
> +	const struct of_device_id *match =
> +		of_match_node(qnap_power_off_of_match_table, np);
> +	cfg = (struct power_off_cfg *)match->data;

This cast is not necessary.
>
>  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>  	if (!res) {
>  		dev_err(&pdev->dev, "Missing resource");
> @@ -94,10 +124,6 @@ static int qnap_power_off_remove(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static const struct of_device_id qnap_power_off_of_match_table[] = {
> -	{ .compatible = "qnap,power-off", },
> -	{}
> -};
>  MODULE_DEVICE_TABLE(of, qnap_power_off_of_match_table);

You should probably move this up above with the table.

  Josh