diff mbox series

[V3,2/4] backlight: qcom-wled: Add callback functions

Message ID 1583760362-26978-3-git-send-email-kgunda@codeaurora.org (mailing list archive)
State Superseded
Headers show
Series Add support for WLED5 | expand

Commit Message

Kiran Gunda March 9, 2020, 1:26 p.m. UTC 
Add cabc_config, sync_toggle, wled_ovp_fault_status and wled_ovp_delay
callback functions to prepare the driver for adding WLED5 support.

Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
---
 drivers/video/backlight/qcom-wled.c | 196 +++++++++++++++++++++++-------------
 1 file changed, 126 insertions(+), 70 deletions(-)

Comments

Daniel Thompson March 10, 2020, 3:27 p.m. UTC | #1 
On Mon, Mar 09, 2020 at 06:56:00PM +0530, Kiran Gunda wrote:
> Add cabc_config, sync_toggle, wled_ovp_fault_status and wled_ovp_delay
> callback functions to prepare the driver for adding WLED5 support.
> 
> Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>

Overall this code would a lot easier to review if
> ---
>  drivers/video/backlight/qcom-wled.c | 196 +++++++++++++++++++++++-------------
>  1 file changed, 126 insertions(+), 70 deletions(-)
> 
> diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
> index 3d276b3..b73f273 100644
> --- a/drivers/video/backlight/qcom-wled.c
> +++ b/drivers/video/backlight/qcom-wled.c
> @@ -128,6 +128,7 @@ struct wled_config {
>  	bool cs_out_en;
>  	bool ext_gen;
>  	bool cabc;
> +	bool en_cabc;

Does this ever get set to true?

>  	bool external_pfet;
>  	bool auto_detection_enabled;
>  };
> @@ -147,14 +148,20 @@ struct wled {
>  	u32 max_brightness;
>  	u32 short_count;
>  	u32 auto_detect_count;
> +	u32 version;
>  	bool disabled_by_short;
>  	bool has_short_detect;
> +	bool cabc_disabled;
>  	int short_irq;
>  	int ovp_irq;
>  
>  	struct wled_config cfg;
>  	struct delayed_work ovp_work;
>  	int (*wled_set_brightness)(struct wled *wled, u16 brightness);
> +	int (*cabc_config)(struct wled *wled, bool enable);
> +	int (*wled_sync_toggle)(struct wled *wled);
> +	int (*wled_ovp_fault_status)(struct wled *wled, bool *fault_set);
> +	int (*wled_ovp_delay)(struct wled *wled);

Let's get some doc comments explaining what these callbacks do (and
which versions they apply to).

cabc_config() in particular appears to have a very odd interface for
wled4.  It looks like it relies on being initially called with enable
set a particular way and prevents itself from acting again. Therefore if
the comment you end up writing doesn't sound "right" then please also
fix the API!

Finally, why is everything except cabc_config() prefixed with wled?


Daniel.
Kiran Gunda March 11, 2020, 6:41 a.m. UTC | #2 
On 2020-03-10 20:57, Daniel Thompson wrote:
> On Mon, Mar 09, 2020 at 06:56:00PM +0530, Kiran Gunda wrote:
>> Add cabc_config, sync_toggle, wled_ovp_fault_status and wled_ovp_delay
>> callback functions to prepare the driver for adding WLED5 support.
>> 
>> Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
> 
> Overall this code would a lot easier to review if
>> ---
>>  drivers/video/backlight/qcom-wled.c | 196 
>> +++++++++++++++++++++++-------------
>>  1 file changed, 126 insertions(+), 70 deletions(-)
>> 
>> diff --git a/drivers/video/backlight/qcom-wled.c 
>> b/drivers/video/backlight/qcom-wled.c
>> index 3d276b3..b73f273 100644
>> --- a/drivers/video/backlight/qcom-wled.c
>> +++ b/drivers/video/backlight/qcom-wled.c
>> @@ -128,6 +128,7 @@ struct wled_config {
>>  	bool cs_out_en;
>>  	bool ext_gen;
>>  	bool cabc;
>> +	bool en_cabc;
> 
> Does this ever get set to true?
> 
Yes. If user wants use the cabc pin to control the brightness and
use the "qcom,cabc" DT property in the device tree.

>>  	bool external_pfet;
>>  	bool auto_detection_enabled;
>>  };
>> @@ -147,14 +148,20 @@ struct wled {
>>  	u32 max_brightness;
>>  	u32 short_count;
>>  	u32 auto_detect_count;
>> +	u32 version;
>>  	bool disabled_by_short;
>>  	bool has_short_detect;
>> +	bool cabc_disabled;
>>  	int short_irq;
>>  	int ovp_irq;
>> 
>>  	struct wled_config cfg;
>>  	struct delayed_work ovp_work;
>>  	int (*wled_set_brightness)(struct wled *wled, u16 brightness);
>> +	int (*cabc_config)(struct wled *wled, bool enable);
>> +	int (*wled_sync_toggle)(struct wled *wled);
>> +	int (*wled_ovp_fault_status)(struct wled *wled, bool *fault_set);
>> +	int (*wled_ovp_delay)(struct wled *wled);
> 
> Let's get some doc comments explaining what these callbacks do (and
> which versions they apply to).
> 
Sure. I will update it in the commit text in next post.

> cabc_config() in particular appears to have a very odd interface for
> wled4.  It looks like it relies on being initially called with enable
> set a particular way and prevents itself from acting again. Therefore 
> if
> the comment you end up writing doesn't sound "right" then please also
> fix the API!
> 
Actually this variable is useful for WLED5, where the default HW state 
is
CABC1 enabled mode. So, if the user doesn't want to use the CABC we are 
configuring
the HW state to "0" based on the DT property and then setting a flag to 
not enable it again.
This is not needed for WLED4. I will remove it for WLED4 in next post.

> Finally, why is everything except cabc_config() prefixed with wled?
> 
It is typo. I will correct it in the next post.
> 
> Daniel.
Daniel Thompson March 11, 2020, 10:30 a.m. UTC | #3 
On Wed, Mar 11, 2020 at 12:11:00PM +0530, kgunda@codeaurora.org wrote:
> On 2020-03-10 20:57, Daniel Thompson wrote:
> > On Mon, Mar 09, 2020 at 06:56:00PM +0530, Kiran Gunda wrote:
> > > Add cabc_config, sync_toggle, wled_ovp_fault_status and wled_ovp_delay
> > > callback functions to prepare the driver for adding WLED5 support.
> > > 
> > > Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
> > 
> > Overall this code would a lot easier to review if
> > > ---
> > >  drivers/video/backlight/qcom-wled.c | 196
> > > +++++++++++++++++++++++-------------
> > >  1 file changed, 126 insertions(+), 70 deletions(-)
> > > 
> > > diff --git a/drivers/video/backlight/qcom-wled.c
> > > b/drivers/video/backlight/qcom-wled.c
> > > index 3d276b3..b73f273 100644
> > > --- a/drivers/video/backlight/qcom-wled.c
> > > +++ b/drivers/video/backlight/qcom-wled.c
> > > @@ -128,6 +128,7 @@ struct wled_config {
> > >  	bool cs_out_en;
> > >  	bool ext_gen;
> > >  	bool cabc;
> > > +	bool en_cabc;
> > 
> > Does this ever get set to true?
> > 
> Yes. If user wants use the cabc pin to control the brightness and
> use the "qcom,cabc" DT property in the device tree.

That sounds like what you intended the code to do!

Is the code that does this present in the patch? I could not find
it.


Daniel.
Kiran Gunda March 23, 2020, 3:36 p.m. UTC | #4 
On 2020-03-11 16:00, Daniel Thompson wrote:
> On Wed, Mar 11, 2020 at 12:11:00PM +0530, kgunda@codeaurora.org wrote:
>> On 2020-03-10 20:57, Daniel Thompson wrote:
>> > On Mon, Mar 09, 2020 at 06:56:00PM +0530, Kiran Gunda wrote:
>> > > Add cabc_config, sync_toggle, wled_ovp_fault_status and wled_ovp_delay
>> > > callback functions to prepare the driver for adding WLED5 support.
>> > >
>> > > Signed-off-by: Kiran Gunda <kgunda@codeaurora.org>
>> >
>> > Overall this code would a lot easier to review if
>> > > ---
>> > >  drivers/video/backlight/qcom-wled.c | 196
>> > > +++++++++++++++++++++++-------------
>> > >  1 file changed, 126 insertions(+), 70 deletions(-)
>> > >
>> > > diff --git a/drivers/video/backlight/qcom-wled.c
>> > > b/drivers/video/backlight/qcom-wled.c
>> > > index 3d276b3..b73f273 100644
>> > > --- a/drivers/video/backlight/qcom-wled.c
>> > > +++ b/drivers/video/backlight/qcom-wled.c
>> > > @@ -128,6 +128,7 @@ struct wled_config {
>> > >  	bool cs_out_en;
>> > >  	bool ext_gen;
>> > >  	bool cabc;
>> > > +	bool en_cabc;
>> >
>> > Does this ever get set to true?
>> >
>> Yes. If user wants use the cabc pin to control the brightness and
>> use the "qcom,cabc" DT property in the device tree.
> 
> That sounds like what you intended the code to do!
> 
> Is the code that does this present in the patch? I could not find
> it.
> 
okay... It's my bad. We already have the "cabc" for this. I will remove 
the en_cabc in
next series.
> 
> Daniel.
diff mbox series

Patch

diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
index 3d276b3..b73f273 100644
--- a/drivers/video/backlight/qcom-wled.c
+++ b/drivers/video/backlight/qcom-wled.c
@@ -128,6 +128,7 @@  struct wled_config {
 	bool cs_out_en;
 	bool ext_gen;
 	bool cabc;
+	bool en_cabc;
 	bool external_pfet;
 	bool auto_detection_enabled;
 };
@@ -147,14 +148,20 @@  struct wled {
 	u32 max_brightness;
 	u32 short_count;
 	u32 auto_detect_count;
+	u32 version;
 	bool disabled_by_short;
 	bool has_short_detect;
+	bool cabc_disabled;
 	int short_irq;
 	int ovp_irq;
 
 	struct wled_config cfg;
 	struct delayed_work ovp_work;
 	int (*wled_set_brightness)(struct wled *wled, u16 brightness);
+	int (*cabc_config)(struct wled *wled, bool enable);
+	int (*wled_sync_toggle)(struct wled *wled);
+	int (*wled_ovp_fault_status)(struct wled *wled, bool *fault_set);
+	int (*wled_ovp_delay)(struct wled *wled);
 };
 
 static int wled3_set_brightness(struct wled *wled, u16 brightness)
@@ -237,7 +244,7 @@  static int wled_module_enable(struct wled *wled, int val)
 	return 0;
 }
 
-static int wled_sync_toggle(struct wled *wled)
+static int wled3_sync_toggle(struct wled *wled)
 {
 	int rc;
 	unsigned int mask = GENMASK(wled->max_string_count - 1, 0);
@@ -255,6 +262,46 @@  static int wled_sync_toggle(struct wled *wled)
 	return rc;
 }
 
+static int wled4_ovp_fault_status(struct wled *wled, bool *fault_set)
+{
+	int rc;
+	u32 int_rt_sts, fault_sts;
+
+	*fault_set = false;
+	rc = regmap_read(wled->regmap,
+			wled->ctrl_addr + WLED3_CTRL_REG_INT_RT_STS,
+			&int_rt_sts);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to read INT_RT_STS rc=%d\n", rc);
+		return rc;
+	}
+
+	rc = regmap_read(wled->regmap,
+			wled->ctrl_addr + WLED3_CTRL_REG_FAULT_STATUS,
+			&fault_sts);
+	if (rc < 0) {
+		dev_err(wled->dev, "Failed to read FAULT_STATUS rc=%d\n", rc);
+		return rc;
+	}
+
+	if (int_rt_sts & WLED3_CTRL_REG_OVP_FAULT_STATUS)
+		*fault_set = true;
+
+	if (fault_sts & WLED3_CTRL_REG_OVP_FAULT_BIT)
+		*fault_set = true;
+
+	if (*fault_set)
+		dev_dbg(wled->dev, "WLED OVP fault detected, int_rt_sts=0x%x fault_sts=0x%x\n",
+			int_rt_sts, fault_sts);
+
+	return rc;
+}
+
+static int wled4_ovp_delay(struct wled *wled)
+{
+	return WLED_SOFT_START_DLY_US;
+}
+
 static int wled_update_status(struct backlight_device *bl)
 {
 	struct wled *wled = bl_get_data(bl);
@@ -275,7 +322,7 @@  static int wled_update_status(struct backlight_device *bl)
 			goto unlock_mutex;
 		}
 
-		rc = wled_sync_toggle(wled);
+		rc = wled->wled_sync_toggle(wled);
 		if (rc < 0) {
 			dev_err(wled->dev, "wled sync failed rc:%d\n", rc);
 			goto unlock_mutex;
@@ -298,6 +345,31 @@  static int wled_update_status(struct backlight_device *bl)
 	return rc;
 }
 
+static int wled4_cabc_config(struct wled *wled, bool enable)
+{
+	int i, j, rc;
+	u8 val;
+
+	if (wled->cabc_disabled)
+		return 0;
+
+	for (i = 0; i < wled->cfg.num_strings; i++) {
+		j = wled->cfg.enabled_strings[i];
+
+		val = enable ? WLED4_SINK_REG_STR_CABC_MASK : 0;
+		rc = regmap_update_bits(wled->regmap, wled->sink_addr +
+					WLED4_SINK_REG_STR_CABC(j),
+					WLED4_SINK_REG_STR_CABC_MASK, val);
+		if (rc < 0)
+			return rc;
+	}
+
+	if (!wled->cfg.en_cabc)
+		wled->cabc_disabled = true;
+
+	return 0;
+}
+
 #define WLED_SHORT_DLY_MS			20
 #define WLED_SHORT_CNT_MAX			5
 #define WLED_SHORT_RESET_CNT_DLY_US		USEC_PER_SEC
@@ -345,9 +417,10 @@  static irqreturn_t wled_short_irq_handler(int irq, void *_wled)
 
 static void wled_auto_string_detection(struct wled *wled)
 {
-	int rc = 0, i;
-	u32 sink_config = 0, int_sts;
+	int rc = 0, i, delay_time_us;
+	u32 sink_config = 0;
 	u8 sink_test = 0, sink_valid = 0, val;
+	bool fault_set;
 
 	/* Read configured sink configuration */
 	rc = regmap_read(wled->regmap, wled->sink_addr +
@@ -376,14 +449,9 @@  static void wled_auto_string_detection(struct wled *wled)
 	}
 
 	if (wled->cfg.cabc) {
-		for (i = 0; i < wled->cfg.num_strings; i++) {
-			rc = regmap_update_bits(wled->regmap, wled->sink_addr +
-						WLED4_SINK_REG_STR_CABC(i),
-						WLED4_SINK_REG_STR_CABC_MASK,
-						0);
-			if (rc < 0)
-				goto failed_detect;
-		}
+		rc = wled->cabc_config(wled, 0);
+		if (rc < 0)
+			goto failed_detect;
 	}
 
 	/* Disable all sinks */
@@ -427,18 +495,17 @@  static void wled_auto_string_detection(struct wled *wled)
 			goto failed_detect;
 		}
 
-		usleep_range(WLED_SOFT_START_DLY_US,
-			     WLED_SOFT_START_DLY_US + 1000);
+		delay_time_us = wled->wled_ovp_delay(wled);
+		usleep_range(delay_time_us, delay_time_us + 1000);
 
-		rc = regmap_read(wled->regmap, wled->ctrl_addr +
-				 WLED3_CTRL_REG_INT_RT_STS, &int_sts);
+		rc = wled->wled_ovp_fault_status(wled, &fault_set);
 		if (rc < 0) {
-			dev_err(wled->dev, "Error in reading WLED3_CTRL_INT_RT_STS rc=%d\n",
+			dev_err(wled->dev, "Error in getting OVP fault_sts, rc=%d\n",
 				rc);
 			goto failed_detect;
 		}
 
-		if (int_sts & WLED3_CTRL_REG_OVP_FAULT_STATUS)
+		if (fault_set)
 			dev_dbg(wled->dev, "WLED OVP fault detected with SINK %d\n",
 				i + 1);
 		else
@@ -478,30 +545,30 @@  static void wled_auto_string_detection(struct wled *wled)
 	}
 
 	/* Enable valid sinks */
-	for (i = 0; i < wled->cfg.num_strings; i++) {
-		if (wled->cfg.cabc) {
-			rc = regmap_update_bits(wled->regmap, wled->sink_addr +
-						WLED4_SINK_REG_STR_CABC(i),
-						WLED4_SINK_REG_STR_CABC_MASK,
-						WLED4_SINK_REG_STR_CABC_MASK);
-			if (rc < 0)
+	if (wled->version == 4) {
+		for (i = 0; i < wled->cfg.num_strings; i++) {
+			if (sink_config &
+			    BIT(WLED4_SINK_REG_CURR_SINK_SHFT + i))
+				val = WLED4_SINK_REG_STR_MOD_MASK;
+			else
+				/* Disable modulator_en for unused sink */
+				val = 0x0;
+
+			rc = regmap_write(wled->regmap, wled->sink_addr +
+					  WLED4_SINK_REG_STR_MOD_EN(i), val);
+			if (rc < 0) {
+				dev_err(wled->dev, "Failed to configure MODULATOR_EN rc=%d\n",
+					rc);
 				goto failed_detect;
-		}
-
-		if (sink_config & BIT(WLED4_SINK_REG_CURR_SINK_SHFT + i))
-			val = WLED4_SINK_REG_STR_MOD_MASK;
-		else
-			val = 0x0; /* Disable modulator_en for unused sink */
-
-		rc = regmap_write(wled->regmap, wled->sink_addr +
-				  WLED4_SINK_REG_STR_MOD_EN(i), val);
-		if (rc < 0) {
-			dev_err(wled->dev, "Failed to configure MODULATOR_EN rc=%d\n",
-				rc);
-			goto failed_detect;
+			}
 		}
 	}
 
+	/* Enable CABC if it needs to be enabled */
+	rc = wled->cabc_config(wled, true);
+	if (rc < 0)
+		goto failed_detect;
+
 	/* Restore the feedback setting */
 	rc = regmap_write(wled->regmap,
 			  wled->ctrl_addr + WLED3_CTRL_REG_FEEDBACK_CONTROL, 0);
@@ -570,29 +637,19 @@  static bool wled_auto_detection_required(struct wled *wled)
 static int wled_auto_detection_at_init(struct wled *wled)
 {
 	int rc;
-	u32 fault_status, rt_status;
+	bool fault_set;
 
 	if (!wled->cfg.auto_detection_enabled)
 		return 0;
 
-	rc = regmap_read(wled->regmap,
-			 wled->ctrl_addr + WLED3_CTRL_REG_INT_RT_STS,
-			 &rt_status);
+	rc = wled->wled_ovp_fault_status(wled, &fault_set);
 	if (rc < 0) {
-		dev_err(wled->dev, "Failed to read RT status rc=%d\n", rc);
-		return rc;
-	}
-
-	rc = regmap_read(wled->regmap,
-			 wled->ctrl_addr + WLED3_CTRL_REG_FAULT_STATUS,
-			 &fault_status);
-	if (rc < 0) {
-		dev_err(wled->dev, "Failed to read fault status rc=%d\n", rc);
+		dev_err(wled->dev, "Error in getting OVP fault_sts, rc=%d\n",
+			rc);
 		return rc;
 	}
 
-	if ((rt_status & WLED3_CTRL_REG_OVP_FAULT_STATUS) ||
-	    (fault_status & WLED3_CTRL_REG_OVP_FAULT_BIT)) {
+	if (fault_set) {
 		mutex_lock(&wled->lock);
 		wled_auto_string_detection(wled);
 		mutex_unlock(&wled->lock);
@@ -811,17 +868,12 @@  static int wled4_setup(struct wled *wled)
 					wled->cfg.string_i_limit);
 		if (rc < 0)
 			return rc;
-
-		addr = wled->sink_addr +
-				WLED4_SINK_REG_STR_CABC(j);
-		rc = regmap_update_bits(wled->regmap, addr,
-					WLED4_SINK_REG_STR_CABC_MASK,
-					wled->cfg.cabc ?
-					WLED4_SINK_REG_STR_CABC_MASK : 0);
-		if (rc < 0)
-			return rc;
 	}
 
+	rc = wled4_cabc_config(wled, wled->cfg.en_cabc);
+	if (rc < 0)
+		return rc;
+
 	rc = regmap_update_bits(wled->regmap, wled->ctrl_addr +
 				WLED3_CTRL_REG_MOD_EN,
 				WLED3_CTRL_REG_MOD_EN_MASK,
@@ -835,7 +887,7 @@  static int wled4_setup(struct wled *wled)
 	if (rc < 0)
 		return rc;
 
-	rc = wled_sync_toggle(wled);
+	rc = wled->wled_sync_toggle(wled);
 	if (rc < 0) {
 		dev_err(wled->dev, "Failed to toggle sync reg rc:%d\n", rc);
 		return rc;
@@ -951,7 +1003,7 @@  static u32 wled_values(const struct wled_var_cfg *cfg, u32 idx)
 	return idx;
 }
 
-static int wled_configure(struct wled *wled, int version)
+static int wled_configure(struct wled *wled)
 {
 	struct wled_config *cfg = &wled->cfg;
 	struct device *dev = wled->dev;
@@ -1035,12 +1087,13 @@  static int wled_configure(struct wled *wled, int version)
 	if (rc)
 		wled->name = devm_kasprintf(dev, GFP_KERNEL, "%pOFn", dev->of_node);
 
-	switch (version) {
+	switch (wled->version) {
 	case 3:
 		u32_opts = wled3_opts;
 		size = ARRAY_SIZE(wled3_opts);
 		*cfg = wled3_config_defaults;
 		wled->wled_set_brightness = wled3_set_brightness;
+		wled->wled_sync_toggle = wled3_sync_toggle;
 		wled->max_string_count = 3;
 		wled->sink_addr = wled->ctrl_addr;
 		break;
@@ -1050,6 +1103,10 @@  static int wled_configure(struct wled *wled, int version)
 		size = ARRAY_SIZE(wled4_opts);
 		*cfg = wled4_config_defaults;
 		wled->wled_set_brightness = wled4_set_brightness;
+		wled->wled_sync_toggle = wled3_sync_toggle;
+		wled->cabc_config = wled4_cabc_config;
+		wled->wled_ovp_fault_status = wled4_ovp_fault_status;
+		wled->wled_ovp_delay = wled4_ovp_delay;
 		wled->max_string_count = 4;
 
 		prop_addr = of_get_address(dev->of_node, 1, NULL, NULL);
@@ -1186,7 +1243,6 @@  static int wled_probe(struct platform_device *pdev)
 	struct backlight_device *bl;
 	struct wled *wled;
 	struct regmap *regmap;
-	int version;
 	u32 val;
 	int rc;
 
@@ -1203,18 +1259,18 @@  static int wled_probe(struct platform_device *pdev)
 	wled->regmap = regmap;
 	wled->dev = &pdev->dev;
 
-	version = (uintptr_t)of_device_get_match_data(&pdev->dev);
-	if (!version) {
+	wled->version = (uintptr_t)of_device_get_match_data(&pdev->dev);
+	if (!wled->version) {
 		dev_err(&pdev->dev, "Unknown device version\n");
 		return -ENODEV;
 	}
 
 	mutex_init(&wled->lock);
-	rc = wled_configure(wled, version);
+	rc = wled_configure(wled);
 	if (rc)
 		return rc;
 
-	switch (version) {
+	switch (wled->version) {
 	case 3:
 		wled->cfg.auto_detection_enabled = false;
 		rc = wled3_setup(wled);