Hi Vivien,
On Wed, Jun 17, 2015 at 06:58:59PM -0400, Vivien Didelot wrote:
> Introduce a new struct max63xx_platform_data to support MAX63xx watchdog
> chips connected via GPIO. A platform code can fill this structure with
> GPIO numbers for WDI and WDSET pins to enable GPIO support in the code.
>
> The driver takes care of requesting and releasing the GPIOs.
>
> Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
would it be possible to use gpiod functions ?
> ---
> drivers/watchdog/Kconfig | 2 +-
> drivers/watchdog/max63xx_wdt.c | 53 ++++++++++++++++++++++++++++++-
> include/linux/platform_data/max63xx_wdt.h | 27 ++++++++++++++++
> 3 files changed, 80 insertions(+), 2 deletions(-)
> create mode 100644 include/linux/platform_data/max63xx_wdt.h
>
> diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
> index 742fbbc..bb65b20 100644
> --- a/drivers/watchdog/Kconfig
> +++ b/drivers/watchdog/Kconfig
> @@ -418,7 +418,7 @@ config TS72XX_WATCHDOG
>
> config MAX63XX_WATCHDOG
> tristate "Max63xx watchdog"
> - depends on HAS_IOMEM
> + depends on HAS_IOMEM || GPIOLIB
> select WATCHDOG_CORE
> help
> Support for memory mapped max63{69,70,71,72,73,74} watchdog timer.
> diff --git a/drivers/watchdog/max63xx_wdt.c b/drivers/watchdog/max63xx_wdt.c
> index 3f7e8d5..cce2b12 100644
> --- a/drivers/watchdog/max63xx_wdt.c
> +++ b/drivers/watchdog/max63xx_wdt.c
> @@ -22,6 +22,8 @@
> #include <linux/watchdog.h>
> #include <linux/bitops.h>
> #include <linux/platform_device.h>
> +#include <linux/platform_data/max63xx_wdt.h>
> +#include <linux/gpio.h>
> #include <linux/spinlock.h>
> #include <linux/io.h>
> #include <linux/slab.h>
> @@ -47,6 +49,9 @@ struct max63xx_wdt {
> struct watchdog_device wdd;
> const struct max63xx_timeout *timeout;
>
> + /* platform settings e.g. GPIO */
> + struct max63xx_platform_data *pdata;
> +
> /* memory mapping */
> void __iomem *base;
> spinlock_t lock;
> @@ -199,6 +204,48 @@ static int max63xx_mmap_init(struct platform_device *p, struct max63xx_wdt *wdt)
> return 0;
> }
>
> +static void max63xx_gpio_ping(struct max63xx_wdt *wdt)
> +{
> + gpio_set_value_cansleep(wdt->pdata->wdi, 1);
> + gpio_set_value_cansleep(wdt->pdata->wdi, 0);
> +}
> +
> +static void max63xx_gpio_set(struct max63xx_wdt *wdt, u8 set)
> +{
> + gpio_set_value_cansleep(wdt->pdata->set0, set & BIT(0));
> + gpio_set_value_cansleep(wdt->pdata->set1, set & BIT(1));
> + gpio_set_value_cansleep(wdt->pdata->set2, set & BIT(2));
> +}
> +
> +static int max63xx_gpio_init(struct platform_device *p, struct max63xx_wdt *wdt)
> +{
> + int err;
> +
> + err = devm_gpio_request_one(&p->dev, wdt->pdata->wdi,
> + GPIOF_OUT_INIT_LOW, "max63xx_wdt WDI");
> + if (err)
> + return err;
> +
> + err = devm_gpio_request_one(&p->dev, wdt->pdata->set0,
> + GPIOF_OUT_INIT_LOW, "max63xx_wdt SET0");
> + if (err)
> + return err;
> +
> + err = devm_gpio_request_one(&p->dev, wdt->pdata->set1,
> + GPIOF_OUT_INIT_LOW, "max63xx_wdt SET1");
> + if (err)
> + return err;
> +
> + err = devm_gpio_request_one(&p->dev, wdt->pdata->set2,
> + GPIOF_OUT_INIT_LOW, "max63xx_wdt SET2");
> + if (err)
> + return err;
> +
> + wdt->ping = max63xx_gpio_ping;
> + wdt->set = max63xx_gpio_set;
> + return 0;
> +}
> +
> static int max63xx_wdt_probe(struct platform_device *pdev)
> {
> struct max63xx_wdt *wdt;
> @@ -211,6 +258,8 @@ static int max63xx_wdt_probe(struct platform_device *pdev)
>
> table = (struct max63xx_timeout *)pdev->id_entry->driver_data;
>
> + wdt->pdata = dev_get_platdata(&pdev->dev);
> +
> if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
> heartbeat = DEFAULT_HEARTBEAT;
>
> @@ -221,7 +270,9 @@ static int max63xx_wdt_probe(struct platform_device *pdev)
> return -EINVAL;
> }
>
> - err = max63xx_mmap_init(pdev, wdt);
> + /* GPIO or memory mapped? */
> + err = wdt->pdata && wdt->pdata->wdi ? max63xx_gpio_init(pdev, wdt) :
> + max63xx_mmap_init(pdev, wdt);
I would prefer something like
if (wdt->pdata && wdt->pdata->wdi)
err = max63xx_gpio_init(pdev, wdt);
else
err = max63xx_mmap_init(pdev, wdt);
because it is much easier to read.
Also, you might want to use gpio_is_valid(). pin number 0 is a valid pin
for at least some architectures.
Thanks,
Guenter
--
To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in
