2019-07-22 17:29:02

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 0/7] backlight: gpio: simplify the driver

From: Bartosz Golaszewski <[email protected]>

While working on my other series related to gpio-backlight[1] I noticed
that we could simplify the driver if we made the only user of platform
data use GPIO lookups and device properties. This series tries to do
that.

The first patch adds all necessary data structures to ecovec24. Patch
2/7 unifies much of the code for both pdata and non-pdata cases. Patches
3-4/7 remove unused platform data fields. Last three patches contain
additional improvements for the GPIO backlight driver while we're already
modifying it.

I don't have access to this HW but hopefully this works. Only compile
tested.

[1] https://lkml.org/lkml/2019/6/25/900

v1 -> v2:
- rebased on top of v5.3-rc1 and adjusted to the recent changes from Andy
- added additional two patches with minor improvements

Bartosz Golaszewski (7):
sh: ecovec24: add additional properties to the backlight device
backlight: gpio: simplify the platform data handling
sh: ecovec24: don't set unused fields in platform data
backlight: gpio: remove unused fields from platform data
backlight: gpio: remove dev from struct gpio_backlight
backlight: gpio: remove def_value from struct gpio_backlight
backlight: gpio: use a helper variable for &pdev->dev

arch/sh/boards/mach-ecovec24/setup.c | 33 ++++++--
drivers/video/backlight/gpio_backlight.c | 87 ++++++--------------
include/linux/platform_data/gpio_backlight.h | 3 -
3 files changed, 48 insertions(+), 75 deletions(-)

--
2.21.0


2019-07-22 17:29:04

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 1/7] sh: ecovec24: add additional properties to the backlight device

From: Bartosz Golaszewski <[email protected]>

Add a GPIO lookup entry and a device property for GPIO backlight to the
board file. Tie them to the platform device which is now registered using
platform_device_register_full() because of the properties. These changes
are inactive now but will be used once the gpio backlight driver is
modified.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
arch/sh/boards/mach-ecovec24/setup.c | 30 +++++++++++++++++++++++-----
1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/arch/sh/boards/mach-ecovec24/setup.c b/arch/sh/boards/mach-ecovec24/setup.c
index f402aa741bf3..6926bb3865b9 100644
--- a/arch/sh/boards/mach-ecovec24/setup.c
+++ b/arch/sh/boards/mach-ecovec24/setup.c
@@ -371,6 +371,19 @@ static struct platform_device lcdc_device = {
},
};

+static struct gpiod_lookup_table gpio_backlight_lookup = {
+ .dev_id = "gpio-backlight.0",
+ .table = {
+ GPIO_LOOKUP("sh7724_pfc", GPIO_PTR1, NULL, GPIO_ACTIVE_HIGH),
+ { }
+ },
+};
+
+static struct property_entry gpio_backlight_props[] = {
+ PROPERTY_ENTRY_BOOL("default-on"),
+ { }
+};
+
static struct gpio_backlight_platform_data gpio_backlight_data = {
.fbdev = &lcdc_device.dev,
.gpio = GPIO_PTR1,
@@ -378,13 +391,15 @@ static struct gpio_backlight_platform_data gpio_backlight_data = {
.name = "backlight",
};

-static struct platform_device gpio_backlight_device = {
+static const struct platform_device_info gpio_backlight_device_info = {
.name = "gpio-backlight",
- .dev = {
- .platform_data = &gpio_backlight_data,
- },
+ .data = &gpio_backlight_data,
+ .size_data = sizeof(gpio_backlight_data),
+ .properties = gpio_backlight_props,
};

+static struct platform_device *gpio_backlight_device;
+
/* CEU0 */
static struct ceu_platform_data ceu0_pdata = {
.num_subdevs = 2,
@@ -1006,7 +1021,6 @@ static struct platform_device *ecovec_devices[] __initdata = {
&usb1_common_device,
&usbhs_device,
&lcdc_device,
- &gpio_backlight_device,
&keysc_device,
&cn12_power,
#if defined(CONFIG_MMC_SDHI) || defined(CONFIG_MMC_SDHI_MODULE)
@@ -1464,6 +1478,12 @@ static int __init arch_setup(void)
#endif
#endif

+ gpiod_add_lookup_table(&gpio_backlight_lookup);
+ gpio_backlight_device = platform_device_register_full(
+ &gpio_backlight_device_info);
+ if (IS_ERR(gpio_backlight_device))
+ return PTR_ERR(gpio_backlight_device);
+
return platform_add_devices(ecovec_devices,
ARRAY_SIZE(ecovec_devices));
}
--
2.21.0

2019-07-22 17:29:16

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

From: Bartosz Golaszewski <[email protected]>

Instead of dereferencing pdev each time, use a helper variable for
the associated device pointer.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/video/backlight/gpio_backlight.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index cd6a75bca9cc..091ff799659a 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -54,29 +54,32 @@ static const struct backlight_ops gpio_backlight_ops = {

static int gpio_backlight_probe(struct platform_device *pdev)
{
- struct gpio_backlight_platform_data *pdata =
- dev_get_platdata(&pdev->dev);
+ struct gpio_backlight_platform_data *pdata;
struct backlight_properties props;
struct backlight_device *bl;
struct gpio_backlight *gbl;
enum gpiod_flags flags;
+ struct device *dev;
int ret, def_value;

- gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
+ dev = &pdev->dev;
+ pdata = dev_get_platdata(dev);
+
+ gbl = devm_kzalloc(dev, sizeof(*gbl), GFP_KERNEL);
if (gbl == NULL)
return -ENOMEM;

if (pdata)
gbl->fbdev = pdata->fbdev;

- def_value = device_property_read_bool(&pdev->dev, "default-on");
+ def_value = device_property_read_bool(dev, "default-on");
flags = def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;

- gbl->gpiod = devm_gpiod_get(&pdev->dev, NULL, flags);
+ gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
if (IS_ERR(gbl->gpiod)) {
ret = PTR_ERR(gbl->gpiod);
if (ret != -EPROBE_DEFER) {
- dev_err(&pdev->dev,
+ dev_err(dev,
"Error: The gpios parameter is missing or invalid.\n");
}
return ret;
@@ -85,11 +88,10 @@ static int gpio_backlight_probe(struct platform_device *pdev)
memset(&props, 0, sizeof(props));
props.type = BACKLIGHT_RAW;
props.max_brightness = 1;
- bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
- &pdev->dev, gbl, &gpio_backlight_ops,
- &props);
+ bl = devm_backlight_device_register(dev, dev_name(dev), dev, gbl,
+ &gpio_backlight_ops, &props);
if (IS_ERR(bl)) {
- dev_err(&pdev->dev, "failed to register backlight\n");
+ dev_err(dev, "failed to register backlight\n");
return PTR_ERR(bl);
}

--
2.21.0

2019-07-22 17:29:19

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 2/7] backlight: gpio: simplify the platform data handling

From: Bartosz Golaszewski <[email protected]>

Now that the last user of platform data (sh ecovec24) defines a proper
GPIO lookup and sets the 'default-on' device property, we can drop the
platform_data-specific GPIO handling and unify a big chunk of code.

The only field used from the platform data is now the fbdev pointer.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/video/backlight/gpio_backlight.c | 64 +++++-------------------
1 file changed, 13 insertions(+), 51 deletions(-)

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index e84f3087e29f..01262186fa1e 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -55,30 +55,6 @@ static const struct backlight_ops gpio_backlight_ops = {
.check_fb = gpio_backlight_check_fb,
};

-static int gpio_backlight_probe_dt(struct platform_device *pdev,
- struct gpio_backlight *gbl)
-{
- struct device *dev = &pdev->dev;
- enum gpiod_flags flags;
- int ret;
-
- gbl->def_value = device_property_read_bool(dev, "default-on");
- flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
-
- gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
- if (IS_ERR(gbl->gpiod)) {
- ret = PTR_ERR(gbl->gpiod);
-
- if (ret != -EPROBE_DEFER) {
- dev_err(dev,
- "Error: The gpios parameter is missing or invalid.\n");
- }
- return ret;
- }
-
- return 0;
-}
-
static int gpio_backlight_probe(struct platform_device *pdev)
{
struct gpio_backlight_platform_data *pdata =
@@ -86,6 +62,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
struct backlight_properties props;
struct backlight_device *bl;
struct gpio_backlight *gbl;
+ enum gpiod_flags flags;
int ret;

gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
@@ -94,35 +71,20 @@ static int gpio_backlight_probe(struct platform_device *pdev)

gbl->dev = &pdev->dev;

- if (pdev->dev.fwnode) {
- ret = gpio_backlight_probe_dt(pdev, gbl);
- if (ret)
- return ret;
- } else if (pdata) {
- /*
- * Legacy platform data GPIO retrieveal. Do not expand
- * the use of this code path, currently only used by one
- * SH board.
- */
- unsigned long flags = GPIOF_DIR_OUT;
-
+ if (pdata)
gbl->fbdev = pdata->fbdev;
- gbl->def_value = pdata->def_value;
- flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
-
- ret = devm_gpio_request_one(gbl->dev, pdata->gpio, flags,
- pdata ? pdata->name : "backlight");
- if (ret < 0) {
- dev_err(&pdev->dev, "unable to request GPIO\n");
- return ret;
+
+ gbl->def_value = device_property_read_bool(&pdev->dev, "default-on");
+ flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+
+ gbl->gpiod = devm_gpiod_get(&pdev->dev, NULL, flags);
+ if (IS_ERR(gbl->gpiod)) {
+ ret = PTR_ERR(gbl->gpiod);
+ if (ret != -EPROBE_DEFER) {
+ dev_err(&pdev->dev,
+ "Error: The gpios parameter is missing or invalid.\n");
}
- gbl->gpiod = gpio_to_desc(pdata->gpio);
- if (!gbl->gpiod)
- return -EINVAL;
- } else {
- dev_err(&pdev->dev,
- "failed to find platform data or device tree node.\n");
- return -ENODEV;
+ return ret;
}

memset(&props, 0, sizeof(props));
--
2.21.0

2019-07-22 17:30:03

by Daniel Thompson

[permalink] [raw]
Subject: Re: [PATCH v2 2/7] backlight: gpio: simplify the platform data handling

On Mon, Jul 22, 2019 at 05:02:57PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> Now that the last user of platform data (sh ecovec24) defines a proper
> GPIO lookup and sets the 'default-on' device property, we can drop the
> platform_data-specific GPIO handling and unify a big chunk of code.
>
> The only field used from the platform data is now the fbdev pointer.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>

Reviewed-by: Daniel Thompson <[email protected]>


> ---
> drivers/video/backlight/gpio_backlight.c | 64 +++++-------------------
> 1 file changed, 13 insertions(+), 51 deletions(-)
>
> diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
> index e84f3087e29f..01262186fa1e 100644
> --- a/drivers/video/backlight/gpio_backlight.c
> +++ b/drivers/video/backlight/gpio_backlight.c
> @@ -55,30 +55,6 @@ static const struct backlight_ops gpio_backlight_ops = {
> .check_fb = gpio_backlight_check_fb,
> };
>
> -static int gpio_backlight_probe_dt(struct platform_device *pdev,
> - struct gpio_backlight *gbl)
> -{
> - struct device *dev = &pdev->dev;
> - enum gpiod_flags flags;
> - int ret;
> -
> - gbl->def_value = device_property_read_bool(dev, "default-on");
> - flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
> -
> - gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
> - if (IS_ERR(gbl->gpiod)) {
> - ret = PTR_ERR(gbl->gpiod);
> -
> - if (ret != -EPROBE_DEFER) {
> - dev_err(dev,
> - "Error: The gpios parameter is missing or invalid.\n");
> - }
> - return ret;
> - }
> -
> - return 0;
> -}
> -
> static int gpio_backlight_probe(struct platform_device *pdev)
> {
> struct gpio_backlight_platform_data *pdata =
> @@ -86,6 +62,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
> struct backlight_properties props;
> struct backlight_device *bl;
> struct gpio_backlight *gbl;
> + enum gpiod_flags flags;
> int ret;
>
> gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
> @@ -94,35 +71,20 @@ static int gpio_backlight_probe(struct platform_device *pdev)
>
> gbl->dev = &pdev->dev;
>
> - if (pdev->dev.fwnode) {
> - ret = gpio_backlight_probe_dt(pdev, gbl);
> - if (ret)
> - return ret;
> - } else if (pdata) {
> - /*
> - * Legacy platform data GPIO retrieveal. Do not expand
> - * the use of this code path, currently only used by one
> - * SH board.
> - */
> - unsigned long flags = GPIOF_DIR_OUT;
> -
> + if (pdata)
> gbl->fbdev = pdata->fbdev;
> - gbl->def_value = pdata->def_value;
> - flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
> -
> - ret = devm_gpio_request_one(gbl->dev, pdata->gpio, flags,
> - pdata ? pdata->name : "backlight");
> - if (ret < 0) {
> - dev_err(&pdev->dev, "unable to request GPIO\n");
> - return ret;
> +
> + gbl->def_value = device_property_read_bool(&pdev->dev, "default-on");
> + flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
> +
> + gbl->gpiod = devm_gpiod_get(&pdev->dev, NULL, flags);
> + if (IS_ERR(gbl->gpiod)) {
> + ret = PTR_ERR(gbl->gpiod);
> + if (ret != -EPROBE_DEFER) {
> + dev_err(&pdev->dev,
> + "Error: The gpios parameter is missing or invalid.\n");
> }
> - gbl->gpiod = gpio_to_desc(pdata->gpio);
> - if (!gbl->gpiod)
> - return -EINVAL;
> - } else {
> - dev_err(&pdev->dev,
> - "failed to find platform data or device tree node.\n");
> - return -ENODEV;
> + return ret;
> }
>
> memset(&props, 0, sizeof(props));
> --
> 2.21.0
>

2019-07-22 17:30:22

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 5/7] backlight: gpio: remove dev from struct gpio_backlight

From: Bartosz Golaszewski <[email protected]>

This field is unused. Remove it.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/video/backlight/gpio_backlight.c | 4 ----
1 file changed, 4 deletions(-)

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 01262186fa1e..70882556f047 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -19,9 +19,7 @@
#include <linux/slab.h>

struct gpio_backlight {
- struct device *dev;
struct device *fbdev;
-
struct gpio_desc *gpiod;
int def_value;
};
@@ -69,8 +67,6 @@ static int gpio_backlight_probe(struct platform_device *pdev)
if (gbl == NULL)
return -ENOMEM;

- gbl->dev = &pdev->dev;
-
if (pdata)
gbl->fbdev = pdata->fbdev;

--
2.21.0

2019-07-22 17:30:32

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 4/7] backlight: gpio: remove unused fields from platform data

From: Bartosz Golaszewski <[email protected]>

Remove the platform data fields that nobody uses.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
include/linux/platform_data/gpio_backlight.h | 3 ---
1 file changed, 3 deletions(-)

diff --git a/include/linux/platform_data/gpio_backlight.h b/include/linux/platform_data/gpio_backlight.h
index 34179d600360..1a8b5b1946fe 100644
--- a/include/linux/platform_data/gpio_backlight.h
+++ b/include/linux/platform_data/gpio_backlight.h
@@ -9,9 +9,6 @@ struct device;

struct gpio_backlight_platform_data {
struct device *fbdev;
- int gpio;
- int def_value;
- const char *name;
};

#endif
--
2.21.0

2019-07-22 17:30:45

by Daniel Thompson

[permalink] [raw]
Subject: Re: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

On Mon, Jul 22, 2019 at 05:03:02PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> Instead of dereferencing pdev each time, use a helper variable for
> the associated device pointer.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>

Reviewed-by: Daniel Thompson <[email protected]>


> ---
> drivers/video/backlight/gpio_backlight.c | 22 ++++++++++++----------
> 1 file changed, 12 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
> index cd6a75bca9cc..091ff799659a 100644
> --- a/drivers/video/backlight/gpio_backlight.c
> +++ b/drivers/video/backlight/gpio_backlight.c
> @@ -54,29 +54,32 @@ static const struct backlight_ops gpio_backlight_ops = {
>
> static int gpio_backlight_probe(struct platform_device *pdev)
> {
> - struct gpio_backlight_platform_data *pdata =
> - dev_get_platdata(&pdev->dev);
> + struct gpio_backlight_platform_data *pdata;
> struct backlight_properties props;
> struct backlight_device *bl;
> struct gpio_backlight *gbl;
> enum gpiod_flags flags;
> + struct device *dev;
> int ret, def_value;
>
> - gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
> + dev = &pdev->dev;
> + pdata = dev_get_platdata(dev);
> +
> + gbl = devm_kzalloc(dev, sizeof(*gbl), GFP_KERNEL);
> if (gbl == NULL)
> return -ENOMEM;
>
> if (pdata)
> gbl->fbdev = pdata->fbdev;
>
> - def_value = device_property_read_bool(&pdev->dev, "default-on");
> + def_value = device_property_read_bool(dev, "default-on");
> flags = def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
>
> - gbl->gpiod = devm_gpiod_get(&pdev->dev, NULL, flags);
> + gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
> if (IS_ERR(gbl->gpiod)) {
> ret = PTR_ERR(gbl->gpiod);
> if (ret != -EPROBE_DEFER) {
> - dev_err(&pdev->dev,
> + dev_err(dev,
> "Error: The gpios parameter is missing or invalid.\n");
> }
> return ret;
> @@ -85,11 +88,10 @@ static int gpio_backlight_probe(struct platform_device *pdev)
> memset(&props, 0, sizeof(props));
> props.type = BACKLIGHT_RAW;
> props.max_brightness = 1;
> - bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
> - &pdev->dev, gbl, &gpio_backlight_ops,
> - &props);
> + bl = devm_backlight_device_register(dev, dev_name(dev), dev, gbl,
> + &gpio_backlight_ops, &props);
> if (IS_ERR(bl)) {
> - dev_err(&pdev->dev, "failed to register backlight\n");
> + dev_err(dev, "failed to register backlight\n");
> return PTR_ERR(bl);
> }
>
> --
> 2.21.0
>

2019-07-22 18:58:29

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 3/7] sh: ecovec24: don't set unused fields in platform data

From: Bartosz Golaszewski <[email protected]>

Platform data fields other than fbdev are no longer used by the
backlight driver. Remove them.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
arch/sh/boards/mach-ecovec24/setup.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/arch/sh/boards/mach-ecovec24/setup.c b/arch/sh/boards/mach-ecovec24/setup.c
index 6926bb3865b9..64a5a1662b6d 100644
--- a/arch/sh/boards/mach-ecovec24/setup.c
+++ b/arch/sh/boards/mach-ecovec24/setup.c
@@ -386,9 +386,6 @@ static struct property_entry gpio_backlight_props[] = {

static struct gpio_backlight_platform_data gpio_backlight_data = {
.fbdev = &lcdc_device.dev,
- .gpio = GPIO_PTR1,
- .def_value = 1,
- .name = "backlight",
};

static const struct platform_device_info gpio_backlight_device_info = {
--
2.21.0

2019-07-22 18:58:48

by Bartosz Golaszewski

[permalink] [raw]
Subject: [PATCH v2 6/7] backlight: gpio: remove def_value from struct gpio_backlight

From: Bartosz Golaszewski <[email protected]>

This field is unused outside of probe(). There's no need to store it.
We can make it into a local variable.

Signed-off-by: Bartosz Golaszewski <[email protected]>
---
drivers/video/backlight/gpio_backlight.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 70882556f047..cd6a75bca9cc 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -21,7 +21,6 @@
struct gpio_backlight {
struct device *fbdev;
struct gpio_desc *gpiod;
- int def_value;
};

static int gpio_backlight_update_status(struct backlight_device *bl)
@@ -61,7 +60,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
struct backlight_device *bl;
struct gpio_backlight *gbl;
enum gpiod_flags flags;
- int ret;
+ int ret, def_value;

gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
if (gbl == NULL)
@@ -70,8 +69,8 @@ static int gpio_backlight_probe(struct platform_device *pdev)
if (pdata)
gbl->fbdev = pdata->fbdev;

- gbl->def_value = device_property_read_bool(&pdev->dev, "default-on");
- flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
+ def_value = device_property_read_bool(&pdev->dev, "default-on");
+ flags = def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;

gbl->gpiod = devm_gpiod_get(&pdev->dev, NULL, flags);
if (IS_ERR(gbl->gpiod)) {
@@ -94,7 +93,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
return PTR_ERR(bl);
}

- bl->props.brightness = gbl->def_value;
+ bl->props.brightness = def_value;
backlight_update_status(bl);

platform_set_drvdata(pdev, bl);
--
2.21.0

2019-07-22 18:59:55

by Daniel Thompson

[permalink] [raw]
Subject: Re: [PATCH v2 5/7] backlight: gpio: remove dev from struct gpio_backlight

On Mon, Jul 22, 2019 at 05:03:00PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> This field is unused. Remove it.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>

Reviewed-by: Daniel Thompson <[email protected]>


> ---
> drivers/video/backlight/gpio_backlight.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
> index 01262186fa1e..70882556f047 100644
> --- a/drivers/video/backlight/gpio_backlight.c
> +++ b/drivers/video/backlight/gpio_backlight.c
> @@ -19,9 +19,7 @@
> #include <linux/slab.h>
>
> struct gpio_backlight {
> - struct device *dev;
> struct device *fbdev;
> -
> struct gpio_desc *gpiod;
> int def_value;
> };
> @@ -69,8 +67,6 @@ static int gpio_backlight_probe(struct platform_device *pdev)
> if (gbl == NULL)
> return -ENOMEM;
>
> - gbl->dev = &pdev->dev;
> -
> if (pdata)
> gbl->fbdev = pdata->fbdev;
>
> --
> 2.21.0
>

2019-07-22 20:29:08

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 2/7] backlight: gpio: simplify the platform data handling

On Mon, Jul 22, 2019 at 05:02:57PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> Now that the last user of platform data (sh ecovec24) defines a proper
> GPIO lookup and sets the 'default-on' device property, we can drop the
> platform_data-specific GPIO handling and unify a big chunk of code.
>
> The only field used from the platform data is now the fbdev pointer.

> -static int gpio_backlight_probe_dt(struct platform_device *pdev,
> - struct gpio_backlight *gbl)
> -{
> - struct device *dev = &pdev->dev;
> - enum gpiod_flags flags;
> - int ret;
> -
> - gbl->def_value = device_property_read_bool(dev, "default-on");
> - flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
> -
> - gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
> - if (IS_ERR(gbl->gpiod)) {
> - ret = PTR_ERR(gbl->gpiod);
> -
> - if (ret != -EPROBE_DEFER) {
> - dev_err(dev,
> - "Error: The gpios parameter is missing or invalid.\n");
> - }
> - return ret;
> - }
> -
> - return 0;
> -}

Why not leave this function (perhaps with different name)?

--
With Best Regards,
Andy Shevchenko


2019-07-22 20:29:42

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

On Mon, Jul 22, 2019 at 05:03:02PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> Instead of dereferencing pdev each time, use a helper variable for
> the associated device pointer.

> static int gpio_backlight_probe(struct platform_device *pdev)
> {
> - struct gpio_backlight_platform_data *pdata =
> - dev_get_platdata(&pdev->dev);
> + struct gpio_backlight_platform_data *pdata;
> struct backlight_properties props;
> struct backlight_device *bl;
> struct gpio_backlight *gbl;
> enum gpiod_flags flags;
> + struct device *dev;

Can't we do

struct device dev = &pdev->dev;
struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);

? It fits 80 nicely.

--
With Best Regards,
Andy Shevchenko


2019-07-22 20:29:57

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 0/7] backlight: gpio: simplify the driver

On Mon, Jul 22, 2019 at 05:02:55PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <[email protected]>
>
> While working on my other series related to gpio-backlight[1] I noticed
> that we could simplify the driver if we made the only user of platform
> data use GPIO lookups and device properties. This series tries to do
> that.
>
> The first patch adds all necessary data structures to ecovec24. Patch
> 2/7 unifies much of the code for both pdata and non-pdata cases. Patches
> 3-4/7 remove unused platform data fields. Last three patches contain
> additional improvements for the GPIO backlight driver while we're already
> modifying it.
>
> I don't have access to this HW but hopefully this works. Only compile
> tested.
>
> [1] https://lkml.org/lkml/2019/6/25/900

For uncommented ones
Reviewed-by: Andy Shevchenko <[email protected]>

>
> v1 -> v2:
> - rebased on top of v5.3-rc1 and adjusted to the recent changes from Andy
> - added additional two patches with minor improvements
>
> Bartosz Golaszewski (7):
> sh: ecovec24: add additional properties to the backlight device
> backlight: gpio: simplify the platform data handling
> sh: ecovec24: don't set unused fields in platform data
> backlight: gpio: remove unused fields from platform data
> backlight: gpio: remove dev from struct gpio_backlight
> backlight: gpio: remove def_value from struct gpio_backlight
> backlight: gpio: use a helper variable for &pdev->dev
>
> arch/sh/boards/mach-ecovec24/setup.c | 33 ++++++--
> drivers/video/backlight/gpio_backlight.c | 87 ++++++--------------
> include/linux/platform_data/gpio_backlight.h | 3 -
> 3 files changed, 48 insertions(+), 75 deletions(-)
>
> --
> 2.21.0
>

--
With Best Regards,
Andy Shevchenko


2019-07-23 14:29:15

by Bartosz Golaszewski

[permalink] [raw]
Subject: Re: [PATCH v2 2/7] backlight: gpio: simplify the platform data handling

pon., 22 lip 2019 o 18:06 Andy Shevchenko
<[email protected]> napisał(a):
>
> On Mon, Jul 22, 2019 at 05:02:57PM +0200, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <[email protected]>
> >
> > Now that the last user of platform data (sh ecovec24) defines a proper
> > GPIO lookup and sets the 'default-on' device property, we can drop the
> > platform_data-specific GPIO handling and unify a big chunk of code.
> >
> > The only field used from the platform data is now the fbdev pointer.
>
> > -static int gpio_backlight_probe_dt(struct platform_device *pdev,
> > - struct gpio_backlight *gbl)
> > -{
> > - struct device *dev = &pdev->dev;
> > - enum gpiod_flags flags;
> > - int ret;
> > -
> > - gbl->def_value = device_property_read_bool(dev, "default-on");
> > - flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
> > -
> > - gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
> > - if (IS_ERR(gbl->gpiod)) {
> > - ret = PTR_ERR(gbl->gpiod);
> > -
> > - if (ret != -EPROBE_DEFER) {
> > - dev_err(dev,
> > - "Error: The gpios parameter is missing or invalid.\n");
> > - }
> > - return ret;
> > - }
> > -
> > - return 0;
> > -}
>
> Why not leave this function (perhaps with different name)?
>
> --
> With Best Regards,
> Andy Shevchenko
>
>

Why would we do that if the entire probe() function is now less than
50 lines long? Also: it gets inlined by the compiler anyway. It
doesn't make sense IMO.

Bart

2019-07-23 16:11:22

by Bartosz Golaszewski

[permalink] [raw]
Subject: Re: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

pon., 22 lip 2019 o 18:09 Andy Shevchenko
<[email protected]> napisał(a):
>
> On Mon, Jul 22, 2019 at 05:03:02PM +0200, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <[email protected]>
> >
> > Instead of dereferencing pdev each time, use a helper variable for
> > the associated device pointer.
>
> > static int gpio_backlight_probe(struct platform_device *pdev)
> > {
> > - struct gpio_backlight_platform_data *pdata =
> > - dev_get_platdata(&pdev->dev);
> > + struct gpio_backlight_platform_data *pdata;
> > struct backlight_properties props;
> > struct backlight_device *bl;
> > struct gpio_backlight *gbl;
> > enum gpiod_flags flags;
> > + struct device *dev;
>
> Can't we do
>
> struct device dev = &pdev->dev;
> struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);
>
> ? It fits 80 nicely.
>

IMO it's more readable like that with the reverse christmas tree layout.

Bart

2019-07-24 00:41:41

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

On Tue, Jul 23, 2019 at 08:29:52AM +0200, Bartosz Golaszewski wrote:
> pon., 22 lip 2019 o 18:09 Andy Shevchenko
> <[email protected]> napisał(a):
> >
> > On Mon, Jul 22, 2019 at 05:03:02PM +0200, Bartosz Golaszewski wrote:
> > > From: Bartosz Golaszewski <[email protected]>
> > >
> > > Instead of dereferencing pdev each time, use a helper variable for
> > > the associated device pointer.
> >
> > > static int gpio_backlight_probe(struct platform_device *pdev)
> > > {
> > > - struct gpio_backlight_platform_data *pdata =
> > > - dev_get_platdata(&pdev->dev);
> > > + struct gpio_backlight_platform_data *pdata;
> > > struct backlight_properties props;
> > > struct backlight_device *bl;
> > > struct gpio_backlight *gbl;
> > > enum gpiod_flags flags;
> > > + struct device *dev;
> >
> > Can't we do
> >
> > struct device dev = &pdev->dev;
> > struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);
> >
> > ? It fits 80 nicely.
> >
>
> IMO it's more readable like that with the reverse christmas tree layout.

It makes more churn in the original code and for initializers the order is
defined by its nature.

--
With Best Regards,
Andy Shevchenko


2019-07-24 00:41:54

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v2 2/7] backlight: gpio: simplify the platform data handling

On Tue, Jul 23, 2019 at 08:28:00AM +0200, Bartosz Golaszewski wrote:
> pon., 22 lip 2019 o 18:06 Andy Shevchenko
> <[email protected]> napisał(a):
> >
> > On Mon, Jul 22, 2019 at 05:02:57PM +0200, Bartosz Golaszewski wrote:
> > > From: Bartosz Golaszewski <[email protected]>
> > >
> > > Now that the last user of platform data (sh ecovec24) defines a proper
> > > GPIO lookup and sets the 'default-on' device property, we can drop the
> > > platform_data-specific GPIO handling and unify a big chunk of code.
> > >
> > > The only field used from the platform data is now the fbdev pointer.
> >
> > > -static int gpio_backlight_probe_dt(struct platform_device *pdev,
> > > - struct gpio_backlight *gbl)
> > > -{
> > > - struct device *dev = &pdev->dev;
> > > - enum gpiod_flags flags;
> > > - int ret;
> > > -
> > > - gbl->def_value = device_property_read_bool(dev, "default-on");
> > > - flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
> > > -
> > > - gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
> > > - if (IS_ERR(gbl->gpiod)) {
> > > - ret = PTR_ERR(gbl->gpiod);
> > > -
> > > - if (ret != -EPROBE_DEFER) {
> > > - dev_err(dev,
> > > - "Error: The gpios parameter is missing or invalid.\n");
> > > - }
> > > - return ret;
> > > - }
> > > -
> > > - return 0;
> > > -}
> >
> > Why not leave this function (perhaps with different name)?
>
> Why would we do that if the entire probe() function is now less than
> 50 lines long? Also: it gets inlined by the compiler anyway. It
> doesn't make sense IMO.

I'm not against this, perhaps, dropping and moving can be split to two changes.

--
With Best Regards,
Andy Shevchenko


2019-07-24 02:17:43

by Daniel Thompson

[permalink] [raw]
Subject: Re: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

On Tue, Jul 23, 2019 at 08:29:52AM +0200, Bartosz Golaszewski wrote:
> pon., 22 lip 2019 o 18:09 Andy Shevchenko
> <[email protected]> napisał(a):
> >
> > On Mon, Jul 22, 2019 at 05:03:02PM +0200, Bartosz Golaszewski wrote:
> > > From: Bartosz Golaszewski <[email protected]>
> > >
> > > Instead of dereferencing pdev each time, use a helper variable for
> > > the associated device pointer.
> >
> > > static int gpio_backlight_probe(struct platform_device *pdev)
> > > {
> > > - struct gpio_backlight_platform_data *pdata =
> > > - dev_get_platdata(&pdev->dev);
> > > + struct gpio_backlight_platform_data *pdata;
> > > struct backlight_properties props;
> > > struct backlight_device *bl;
> > > struct gpio_backlight *gbl;
> > > enum gpiod_flags flags;
> > > + struct device *dev;
> >
> > Can't we do
> >
> > struct device dev = &pdev->dev;
> > struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);
> >
> > ? It fits 80 nicely.
> >
>
> IMO it's more readable like that with the reverse christmas tree layout.

There is no requirement for reverse christmas tree layout for this area
of the kernel (and especially not where RCTL is used as a justification
to avoid initializers).

I have a weak personal preference for initializers although it is
sufficiently weak I was happy to put a reviewed by on the original
patch without comment.


Daniel.

2019-07-24 08:27:53

by Bartosz Golaszewski

[permalink] [raw]
Subject: Re: [PATCH v2 7/7] backlight: gpio: use a helper variable for &pdev->dev

wt., 23 lip 2019 o 17:34 Andy Shevchenko
<[email protected]> napisał(a):
>
> On Tue, Jul 23, 2019 at 08:29:52AM +0200, Bartosz Golaszewski wrote:
> > pon., 22 lip 2019 o 18:09 Andy Shevchenko
> > <[email protected]> napisał(a):
> > >
> > > On Mon, Jul 22, 2019 at 05:03:02PM +0200, Bartosz Golaszewski wrote:
> > > > From: Bartosz Golaszewski <[email protected]>
> > > >
> > > > Instead of dereferencing pdev each time, use a helper variable for
> > > > the associated device pointer.
> > >
> > > > static int gpio_backlight_probe(struct platform_device *pdev)
> > > > {
> > > > - struct gpio_backlight_platform_data *pdata =
> > > > - dev_get_platdata(&pdev->dev);
> > > > + struct gpio_backlight_platform_data *pdata;
> > > > struct backlight_properties props;
> > > > struct backlight_device *bl;
> > > > struct gpio_backlight *gbl;
> > > > enum gpiod_flags flags;
> > > > + struct device *dev;
> > >
> > > Can't we do
> > >
> > > struct device dev = &pdev->dev;
> > > struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);
> > >
> > > ? It fits 80 nicely.
> > >
> >
> > IMO it's more readable like that with the reverse christmas tree layout.
>
> It makes more churn in the original code and for initializers the order is
> defined by its nature.
>
> --
> With Best Regards,
> Andy Shevchenko
>
>

Fair enough, I changed it in v3.

Bart

2019-07-24 08:28:01

by Bartosz Golaszewski

[permalink] [raw]
Subject: Re: [PATCH v2 2/7] backlight: gpio: simplify the platform data handling

wt., 23 lip 2019 o 17:32 Andy Shevchenko
<[email protected]> napisał(a):
>
> On Tue, Jul 23, 2019 at 08:28:00AM +0200, Bartosz Golaszewski wrote:
> > pon., 22 lip 2019 o 18:06 Andy Shevchenko
> > <[email protected]> napisał(a):
> > >
> > > On Mon, Jul 22, 2019 at 05:02:57PM +0200, Bartosz Golaszewski wrote:
> > > > From: Bartosz Golaszewski <[email protected]>
> > > >
> > > > Now that the last user of platform data (sh ecovec24) defines a proper
> > > > GPIO lookup and sets the 'default-on' device property, we can drop the
> > > > platform_data-specific GPIO handling and unify a big chunk of code.
> > > >
> > > > The only field used from the platform data is now the fbdev pointer.
> > >
> > > > -static int gpio_backlight_probe_dt(struct platform_device *pdev,
> > > > - struct gpio_backlight *gbl)
> > > > -{
> > > > - struct device *dev = &pdev->dev;
> > > > - enum gpiod_flags flags;
> > > > - int ret;
> > > > -
> > > > - gbl->def_value = device_property_read_bool(dev, "default-on");
> > > > - flags = gbl->def_value ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
> > > > -
> > > > - gbl->gpiod = devm_gpiod_get(dev, NULL, flags);
> > > > - if (IS_ERR(gbl->gpiod)) {
> > > > - ret = PTR_ERR(gbl->gpiod);
> > > > -
> > > > - if (ret != -EPROBE_DEFER) {
> > > > - dev_err(dev,
> > > > - "Error: The gpios parameter is missing or invalid.\n");
> > > > - }
> > > > - return ret;
> > > > - }
> > > > -
> > > > - return 0;
> > > > -}
> > >
> > > Why not leave this function (perhaps with different name)?
> >
> > Why would we do that if the entire probe() function is now less than
> > 50 lines long? Also: it gets inlined by the compiler anyway. It
> > doesn't make sense IMO.
>
> I'm not against this, perhaps, dropping and moving can be split to two changes.
>

This really is unnecessary - we can do it in a single patch alright.

Bart

2019-08-05 09:54:57

by Linus Walleij

[permalink] [raw]
Subject: Re: [PATCH v2 1/7] sh: ecovec24: add additional properties to the backlight device

On Mon, Jul 22, 2019 at 5:03 PM Bartosz Golaszewski <[email protected]> wrote:

> From: Bartosz Golaszewski <[email protected]>
>
> Add a GPIO lookup entry and a device property for GPIO backlight to the
> board file. Tie them to the platform device which is now registered using
> platform_device_register_full() because of the properties. These changes
> are inactive now but will be used once the gpio backlight driver is
> modified.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>

Clever! I must also use these dynamic properties now.

Reviewed-by: Linus Walleij <[email protected]>

Yours,
Linus Walleij