Re: [PATCH 4/4] pinctrl: qcom: Add support for reset for apq8064

Bjorn Andersson
2014-08-29T01:28:26Z

On Thu 28 Aug 20:22 PDT 2014, Pramod Gurav wrote:

> This patch adds support for reset functions to reboot the boards
> with soc apq8064.
>
> CC: Linus Walleij <linus.walleij@linaro.org>
> CC: Bjorn Andersson <bjorn.andersson@sonymobile.com>
> CC: "Ivan T. Ivanov" <iivanov@mm-sol.com>
> CC: Stephen Boyd <sboyd@codeaurora.org>
> CC: Andy Gross <agross@codeaurora.org>
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
> ---
> drivers/pinctrl/qcom/pinctrl-apq8064.c | 7 +++++-
> drivers/pinctrl/qcom/pinctrl-msm.c | 38 ++++++++++++++++++++++++++++++++
> 2 files changed, 44 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/pinctrl/qcom/pinctrl-apq8064.c b/drivers/pinctrl/qcom/pinctrl-apq8064.c
> index feb6f15..ef1263c 100644
> --- a/drivers/pinctrl/qcom/pinctrl-apq8064.c
> +++ b/drivers/pinctrl/qcom/pinctrl-apq8064.c
> @@ -324,6 +324,7 @@ enum apq8064_functions {
> APQ_MUX_tsif1,
> APQ_MUX_tsif2,
> APQ_MUX_usb2_hsic,
> + APQ_MUX_ps_hold,
> APQ_MUX_NA,
> };
>
> @@ -351,6 +352,9 @@ static const char * const gpio_groups[] = {
> "gpio78", "gpio79", "gpio80", "gpio81", "gpio82", "gpio83", "gpio84",
> "gpio85", "gpio86", "gpio87", "gpio88", "gpio89"
> };
> +static const char * const ps_hold_groups[] = {
> + "gpio78"
> +};
> static const char * const gsbi1_groups[] = {
> "gpio18", "gpio19", "gpio20", "gpio21"
> };
> @@ -477,6 +481,7 @@ static const struct msm_function apq8064_functions[] = {
> FUNCTION(tsif1),
> FUNCTION(tsif2),
> FUNCTION(usb2_hsic),
> + FUNCTION(ps_hold),
> };
>
> static const struct msm_pingroup apq8064_groups[] = {
> @@ -558,7 +563,7 @@ static const struct msm_pingroup apq8064_groups[] = {
> PINGROUP(75, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> PINGROUP(76, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> PINGROUP(77, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> - PINGROUP(78, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> + PINGROUP(78, ps_hold, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> PINGROUP(79, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> PINGROUP(80, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> PINGROUP(81, NA, NA, NA, NA, NA, NA, NA, NA, NA, NA),
> diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
> index 2738108..be43e7a 100644
> --- a/drivers/pinctrl/qcom/pinctrl-msm.c
> +++ b/drivers/pinctrl/qcom/pinctrl-msm.c
> @@ -12,6 +12,7 @@
> * GNU General Public License for more details.
> */
>
> +#include <linux/delay.h>
> #include <linux/err.h>
> #include <linux/io.h>
> #include <linux/module.h>
> @@ -27,12 +28,17 @@
> #include <linux/interrupt.h>
> #include <linux/spinlock.h>
>
> +#include <asm/system_misc.h>
> +
> #include "../core.h"
> #include "../pinconf.h"
> #include "pinctrl-msm.h"
> #include "../pinctrl-utils.h"
>
> #define MAX_NR_GPIO 300
> +#define PS_HOLD_OFFSET 0x820
> +
> +static void __iomem *msm_ps_hold;
>
> /**
> * struct msm_pinctrl - state for a pinctrl-msm device
> @@ -848,10 +854,31 @@ static int msm_gpio_init(struct msm_pinctrl *pctrl)
> return 0;
> }
>
> +static void qcom_reset(enum reboot_mode reboot_mode, const char *cmd)

This doesn't follow the naming used in this.

> +{
> + writel(0, msm_ps_hold);
> + mdelay(10000);

Why 10 seconds? What happens after that?

> +}
> +
> +const struct msm_function
> +*find_pshold_function(const struct msm_function *functions,
> + unsigned nfunctions, const char *name)

This should be static. But that would cause a compile warning on non-ARM
platforms, see below.

> +{
> + int i = 0;
> + const struct msm_function *func;
> +
> + for (func = functions; i <= nfunctions; func++, i++)

Why do you have 'func' and why do you iterate over that and i?

for (i = 0; i < nfunctions; i++)
if (strcmp(functions[i]->name, name) == 0)
return true; (or &functions[i] if you really need it)

But as you only uses this once I would prefer if you just merge in the setting
of msm_ps_hold and arm_pm_restart here as well, see below.

> + if (!strcmp(func->name, name))
> + return func;
> +
> + return NULL;
> +}
> +
> int msm_pinctrl_probe(struct platform_device *pdev,
> const struct msm_pinctrl_soc_data *soc_data)
> {
> struct msm_pinctrl *pctrl;
> + const struct msm_function *func;
> struct resource *res;
> int ret;
>
> @@ -871,6 +898,17 @@ int msm_pinctrl_probe(struct platform_device *pdev,
> if (IS_ERR(pctrl->regs))
> return PTR_ERR(pctrl->regs);
>
> +#ifdef CONFIG_ARM
> + func = find_pshold_function(soc_data->functions,
> + soc_data->nfunctions, "ps_hold");
> + if (func) {
> + dev_dbg(&pdev->dev, "Found Function %s\n", func->name);

Guess what, it will print "ps_hold" here. I would prefer if you just skip this
line, as this will always be true on 8960 and 8064.

> + msm_ps_hold = pctrl->regs + PS_HOLD_OFFSET;
> + arm_pm_restart = qcom_reset;
> + }
> +#else
> +#error "not supported on this arch"

There is no reason for you to break compilation of this driver on non-ARM
platforms. This #else/#error should be removed.

I would prefer if you did not #ifdef at all within the function, but rather
merge this piece of logic with the search above into a static function that's
surrounded by a check for CONFIG_ARM - providing a no-op for non-arm boards.

I.e

#ifdef CONFIG_ARM
static void qcom_reset(enum reboot_mode reboot_mode, const char *cmd)
{
...
}

static void msm_pinctrl_setup_pm_reset(pctrl)
{
...
}
#else
static void msm_pinctrl_setup_pm_reset(pctrl) {}
#endif

> +#endif

Regards,
Bjorn