| Message ID | 20180117140159.27611-3-daniel.vetter@ffwll.ch (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
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.jones@linaro.org> > Cc: Daniel Thompson <daniel.thompson@linaro.org> > Cc: Jingoo Han <jingoohan1@gmail.com> > Signed-off-by: Daniel Vetter <daniel.vetter@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... > > 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? > 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); > >
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.jones@linaro.org> > > Cc: Daniel Thompson <daniel.thompson@linaro.org> > > Cc: Jingoo Han <jingoohan1@gmail.com> > > Signed-off-by: Daniel Vetter <daniel.vetter@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 :-) > > > > 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); > >
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.jones@linaro.org> >>> Cc: Daniel Thompson <daniel.thompson@linaro.org> >>> Cc: Jingoo Han <jingoohan1@gmail.com> >>> Signed-off-by: Daniel Vetter <daniel.vetter@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.thompson@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); >>> >
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 +}; 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; 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); 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);
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.jones@linaro.org> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Jingoo Han <jingoohan1@gmail.com> Signed-off-by: Daniel Vetter <daniel.vetter@intel.com> --- drivers/video/backlight/pandora_bl.c | 26 +++++++++++++++++++------- 1 file changed, 19 insertions(+), 7 deletions(-)