Re: [PATCH v8 8/9] pwm: pwm-omap-dmtimer: Adapt driver to utilize dmtimer pdata ops

From: Ladislav Michl
Date: Wed Jan 24 2018 - 02:24:56 EST


Keerthy,

On Wed, Jan 24, 2018 at 11:14:40AM +0530, Keerthy wrote:
> Adapt driver to utilize dmtimer pdata ops instead of pdata-quirks.
>
> Signed-off-by: Keerthy <j-keerthy@xxxxxx>
> Acked-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
> Reviewed-by: Claudiu Beznea <claudiu.beznea@xxxxxxxxxxxxx>
> ---
>
> Changes in v8:
>
> * Added of_node_put call in success case of probe.
>
> Boot tested on am437x-gp-evm and dra7xx-evm.
> Also compile tested omap1_defconfig with other patches of v7
> posted here:
>
> https://www.spinics.net/lists/linux-omap/msg141100.html
>
> With v8 version of Patch 8/9.
>
> drivers/pwm/pwm-omap-dmtimer.c | 68 ++++++++++++++++++++++++++----------------
> 1 file changed, 42 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c
> index 5ad42f3..c00e474 100644
> --- a/drivers/pwm/pwm-omap-dmtimer.c
> +++ b/drivers/pwm/pwm-omap-dmtimer.c
> @@ -23,6 +23,7 @@
> #include <linux/mutex.h>
> #include <linux/of.h>
> #include <linux/of_platform.h>
> +#include <linux/platform_data/dmtimer-omap.h>
> #include <linux/platform_data/pwm_omap_dmtimer.h>
> #include <linux/platform_device.h>
> #include <linux/pm_runtime.h>
> @@ -37,7 +38,7 @@ struct pwm_omap_dmtimer_chip {
> struct pwm_chip chip;
> struct mutex mutex;
> pwm_omap_dmtimer *dm_timer;
> - struct pwm_omap_dmtimer_pdata *pdata;
> + struct omap_dm_timer_ops *pdata;
> struct platform_device *dm_timer_pdev;
> };
>
> @@ -242,19 +243,35 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
> {
> struct device_node *np = pdev->dev.of_node;
> struct device_node *timer;
> + struct platform_device *timer_pdev;
> struct pwm_omap_dmtimer_chip *omap;
> - struct pwm_omap_dmtimer_pdata *pdata;
> + struct dmtimer_platform_data *timer_pdata;
> + struct omap_dm_timer_ops *pdata;
> pwm_omap_dmtimer *dm_timer;
> u32 v;
> - int status;
> + int status, ret = 0;
>
> - pdata = dev_get_platdata(&pdev->dev);
> - if (!pdata) {
> - dev_err(&pdev->dev, "Missing dmtimer platform data\n");
> - return -EINVAL;
> + timer = of_parse_phandle(np, "ti,timers", 0);
> + if (!timer)
> + return -ENODEV;
> +
> + timer_pdev = of_find_device_by_node(timer);
> + if (!timer_pdev) {
> + dev_err(&pdev->dev, "Unable to find Timer pdev\n");
> + ret = -ENODEV;
> + goto put;
> }
>
> - if (!pdata->request_by_node ||
> + timer_pdata = dev_get_platdata(&timer_pdev->dev);
> + if (!timer_pdata) {
> + dev_err(&pdev->dev, "dmtimer pdata structure NULL\n");
> + ret = -EINVAL;
> + goto put;
> + }
> +
> + pdata = timer_pdata->timer_ops;
> +
> + if (!pdata || !pdata->request_by_node ||
> !pdata->free ||
> !pdata->enable ||
> !pdata->disable ||
> @@ -267,37 +284,32 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
> !pdata->set_prescaler ||
> !pdata->write_counter) {
> dev_err(&pdev->dev, "Incomplete dmtimer pdata structure\n");
> - return -EINVAL;
> + ret = -EINVAL;
> + goto put;
> }
>
> - timer = of_parse_phandle(np, "ti,timers", 0);
> - if (!timer)
> - return -ENODEV;
> -
> if (!of_get_property(timer, "ti,timer-pwm", NULL)) {
> dev_err(&pdev->dev, "Missing ti,timer-pwm capability\n");
> - return -ENODEV;
> + ret = -ENODEV;
> + goto put;

Should we call of_node_put() even from here? of_get_property() failed, so
reference was not updated.

> }
>
> dm_timer = pdata->request_by_node(timer);

And timer seems to be used only here, so calling
of_node_put(timer);
just here should be enough.

> - if (!dm_timer)
> - return -EPROBE_DEFER;
> + if (!dm_timer) {
> + ret = -EPROBE_DEFER;
> + goto put;
> + }
>
> omap = devm_kzalloc(&pdev->dev, sizeof(*omap), GFP_KERNEL);
> if (!omap) {
> pdata->free(dm_timer);
> - return -ENOMEM;
> + ret = -ENOMEM;
> + goto put;
> }
>
> omap->pdata = pdata;
> omap->dm_timer = dm_timer;
> -
> - omap->dm_timer_pdev = of_find_device_by_node(timer);
> - if (!omap->dm_timer_pdev) {
> - dev_err(&pdev->dev, "Unable to find timer pdev\n");
> - omap->pdata->free(dm_timer);
> - return -EINVAL;
> - }
> + omap->dm_timer_pdev = timer_pdev;
>
> /*
> * Ensure that the timer is stopped before we allow PWM core to call
> @@ -326,12 +338,16 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
> if (status < 0) {
> dev_err(&pdev->dev, "failed to register PWM\n");
> omap->pdata->free(omap->dm_timer);
> - return status;
> + ret = status;
> + goto put;
> }
>
> platform_set_drvdata(pdev, omap);
>
> - return 0;
> +put:
> + of_node_put(timer);
> +
> + return ret;
> }
>
> static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
> --
> 1.9.1