On 17/01/18 21:38, Daniel Vetter wrote:
Thanks a lot for your comments.
On Wed, Jan 17, 2018 at 04:47:41PM +0000, Daniel Thompson wrote:
On 17/01/18 14:01, Daniel Vetter wrote:
Leaking driver internal tracking into the already massively confusing
backlight power tracking is really confusing.
Stop that by allocating a tiny driver private data structure instead.
Cc: Lee Jones <lee.jo...@linaro.org>
Cc: Daniel Thompson <daniel.thomp...@linaro.org>
Cc: Jingoo Han <jingooh...@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vet...@intel.com>
---
drivers/video/backlight/pandora_bl.c | 26 +++++++++++++++++++-------
1 file changed, 19 insertions(+), 7 deletions(-)
diff --git a/drivers/video/backlight/pandora_bl.c
b/drivers/video/backlight/pandora_bl.c
index a186bc677c7d..6bd159946a47 100644
--- a/drivers/video/backlight/pandora_bl.c
+++ b/drivers/video/backlight/pandora_bl.c
@@ -35,11 +35,15 @@
#define MAX_VALUE 63
#define MAX_USER_VALUE (MAX_VALUE - MIN_VALUE)
-#define PANDORABL_WAS_OFF BL_CORE_DRIVER1
+struct pandora_private {
+ unsigned old_state;
+#define PANDORABL_WAS_OFF 1
Nit, but we using old_state like a bitfield so, BIT(0)?
+};
static int pandora_backlight_update_status(struct backlight_device *bl)
{
int brightness = bl->props.brightness;
+ struct pandora_private *priv = bl_get_data(bl);
u8 r;
if (bl->props.power != FB_BLANK_UNBLANK)
@@ -53,7 +57,7 @@ static int pandora_backlight_update_status(struct
backlight_device *bl)
brightness = MAX_USER_VALUE;
if (brightness == 0) {
- if (bl->props.state & PANDORABL_WAS_OFF)
+ if (priv->old_state & PANDORABL_WAS_OFF)
goto done;
/* first disable PWM0 output, then clock */
@@ -66,7 +70,7 @@ static int pandora_backlight_update_status(struct
backlight_device *bl)
goto done;
}
- if (bl->props.state & PANDORABL_WAS_OFF) {
+ if (priv->old_state & PANDORABL_WAS_OFF) {
/*
* set PWM duty cycle to max. TPS61161 seems to use this
* to calibrate it's PWM sensitivity when it starts.
@@ -93,9 +97,9 @@ static int pandora_backlight_update_status(struct
backlight_device *bl)
done:
if (brightness != 0)
- bl->props.state &= ~PANDORABL_WAS_OFF;
+ priv->old_state 0;
else
- bl->props.state |= PANDORABL_WAS_OFF;
+ priv->old_state = PANDORABL_WAS_OFF;
Well, we were using it like a bitfield until this bit...
I had a simple boolean first (because that's all we neeed), but that made
the code less readable. Should I s/1/true/ in the #define? The entire C99
bool tends to be a bit a bikeshed sometimes :-)
I'd prefer a simple boolean or just storing old_brightness directly in
priv... it is only ever consumed as a boolean anyway. I'd have to say
I'm not keen on #define true alongside the existing bitmask checks.
However... I'm happy to leave that with you. Providing the spurious
kfree() is removed then please feel free to repost with:
Acked-by: Daniel Thompson <daniel.thomp...@linaro.org>
Daniel.
return 0;
}
@@ -109,15 +113,23 @@ static int pandora_backlight_probe(struct platform_device
*pdev)
{
struct backlight_properties props;
struct backlight_device *bl;
+ struct pandora_private *priv;
u8 r;
+ priv = devm_kmalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv) {
+ dev_err(&pdev->dev, "failed to allocate driver private data\n");
+ return -ENOMEM;
+ }
+
memset(&props, 0, sizeof(props));
props.max_brightness = MAX_USER_VALUE;
props.type = BACKLIGHT_RAW;
bl = devm_backlight_device_register(&pdev->dev, pdev->name, &pdev->dev,
- NULL, &pandora_backlight_ops, &props);
+ priv, &pandora_backlight_ops, &props);
if (IS_ERR(bl)) {
dev_err(&pdev->dev, "failed to register backlight\n");
+ kfree(priv);
Why can't we rely on devres for cleanup?
Argh, I had kmalloc first and then changed to devm_kmalloc. The kfree here
needs to go indeed.
Cheers, Daniel
return PTR_ERR(bl);
}
@@ -126,7 +138,7 @@ static int pandora_backlight_probe(struct platform_device
*pdev)
/* 64 cycle period, ON position 0 */
twl_i2c_write_u8(TWL_MODULE_PWM, 0x80, TWL_PWM0_ON);
- bl->props.state |= PANDORABL_WAS_OFF;
+ priv->old_state = PANDORABL_WAS_OFF;
bl->props.brightness = MAX_USER_VALUE;
backlight_update_status(bl);
