| Message ID | 20181212014002.4753-1-marek.vasut+renesas@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | [V2,01/14] gpio: pca953x: Deduplicate the bank_shift | expand |
Hi Marek, On 12/12/2018 01:39, Marek Vasut wrote: > The bank_shift = fls(...) code was duplicated in the driver 5 times, > pull it into separate function. > This looks like a good fix-up to me. As it's just a single line, it might have warranted being a macro - but I think the function helps a lot and is readable. The compiler will likely inline it anyway. > Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> > Cc: Linus Walleij <linus.walleij@linaro.org> > Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> > --- > V2: Replace bank_size with bank_shift in commit message > --- > drivers/gpio/gpio-pca953x.c | 18 +++++++++++------- > 1 file changed, 11 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c > index 540166443c34..afe6de4c48c4 100644 > --- a/drivers/gpio/gpio-pca953x.c > +++ b/drivers/gpio/gpio-pca953x.c > @@ -159,11 +159,16 @@ struct pca953x_chip { > int (*read_regs)(struct pca953x_chip *, int, u8 *); > }; > > +static int pca953x_bank_shift(struct pca953x_chip *chip) > +{ > + return fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); > +} > + > static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val, > int off) > { > int ret; > - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); > + int bank_shift = pca953x_bank_shift(chip); > int offset = off / BANK_SZ; > > ret = i2c_smbus_read_byte_data(chip->client, > @@ -182,7 +187,7 @@ static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val, > int off) > { > int ret; > - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); > + int bank_shift = pca953x_bank_shift(chip); > int offset = off / BANK_SZ; > > ret = i2c_smbus_write_byte_data(chip->client, > @@ -221,7 +226,7 @@ static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val) > > static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val) > { > - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); > + int bank_shift = pca953x_bank_shift(chip); > int addr = (reg & PCAL_GPIO_MASK) << bank_shift; > int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1; > > @@ -265,7 +270,7 @@ static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val) > > static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val) > { > - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); > + int bank_shift = pca953x_bank_shift(chip); > int addr = (reg & PCAL_GPIO_MASK) << bank_shift; > int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1; > > @@ -402,13 +407,12 @@ static void pca953x_gpio_set_multiple(struct gpio_chip *gc, > unsigned long *mask, unsigned long *bits) > { > struct pca953x_chip *chip = gpiochip_get_data(gc); > + int bank_shift = pca953x_bank_shift(chip); > unsigned int bank_mask, bank_val; > - int bank_shift, bank; > + int bank; > u8 reg_val[MAX_BANK]; > int ret; > > - bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); > - > mutex_lock(&chip->i2c_lock); > memcpy(reg_val, chip->reg_output, NBANK(chip)); > for (bank = 0; bank < NBANK(chip); bank++) { >
On 12/13/2018 12:03 PM, Kieran Bingham wrote: > Hi Marek, Hi, > On 12/12/2018 01:39, Marek Vasut wrote: >> The bank_shift = fls(...) code was duplicated in the driver 5 times, >> pull it into separate function. >> > > This looks like a good fix-up to me. > > As it's just a single line, it might have warranted being a macro - but > I think the function helps a lot and is readable. The compiler will > likely inline it anyway. The compiler will inline it , and the bonus point is that you get type checking . There is no type checking with a macro. >> Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> > > Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com> > > >> Cc: Linus Walleij <linus.walleij@linaro.org> >> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> >> --- >> V2: Replace bank_size with bank_shift in commit message >> --- >> drivers/gpio/gpio-pca953x.c | 18 +++++++++++------- >> 1 file changed, 11 insertions(+), 7 deletions(-) >> >> diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c >> index 540166443c34..afe6de4c48c4 100644 >> --- a/drivers/gpio/gpio-pca953x.c >> +++ b/drivers/gpio/gpio-pca953x.c >> @@ -159,11 +159,16 @@ struct pca953x_chip { >> int (*read_regs)(struct pca953x_chip *, int, u8 *); >> }; >> >> +static int pca953x_bank_shift(struct pca953x_chip *chip) >> +{ >> + return fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); >> +} >> + >> static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val, >> int off) >> { >> int ret; >> - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); >> + int bank_shift = pca953x_bank_shift(chip); >> int offset = off / BANK_SZ; >> >> ret = i2c_smbus_read_byte_data(chip->client, >> @@ -182,7 +187,7 @@ static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val, >> int off) >> { >> int ret; >> - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); >> + int bank_shift = pca953x_bank_shift(chip); >> int offset = off / BANK_SZ; >> >> ret = i2c_smbus_write_byte_data(chip->client, >> @@ -221,7 +226,7 @@ static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val) >> >> static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val) >> { >> - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); >> + int bank_shift = pca953x_bank_shift(chip); >> int addr = (reg & PCAL_GPIO_MASK) << bank_shift; >> int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1; >> >> @@ -265,7 +270,7 @@ static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val) >> >> static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val) >> { >> - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); >> + int bank_shift = pca953x_bank_shift(chip); >> int addr = (reg & PCAL_GPIO_MASK) << bank_shift; >> int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1; >> >> @@ -402,13 +407,12 @@ static void pca953x_gpio_set_multiple(struct gpio_chip *gc, >> unsigned long *mask, unsigned long *bits) >> { >> struct pca953x_chip *chip = gpiochip_get_data(gc); >> + int bank_shift = pca953x_bank_shift(chip); >> unsigned int bank_mask, bank_val; >> - int bank_shift, bank; >> + int bank; >> u8 reg_val[MAX_BANK]; >> int ret; >> >> - bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); >> - >> mutex_lock(&chip->i2c_lock); >> memcpy(reg_val, chip->reg_output, NBANK(chip)); >> for (bank = 0; bank < NBANK(chip); bank++) { >> > >
I applied the whole series to an immutable branch and pushed to kernelorg for testing in zeroday. If it builds fine I will push it to devel. Must say this series is impressive. It's doing away with a whole slew of "technical debt" (old code not using modern frameworks). Strangely this driver doesn't support any pin config, it even seems to have per-pin debounce and everything. Some can be quickly supported by just adding the .set_config() callback, others like pull up/down are more dubious. If it supports open drain in hardware we should definately make use of it. Just in case you're interested! Yours, Linus Walleij
On 12/14/2018 03:50 PM, Linus Walleij wrote: > I applied the whole series to an immutable branch and pushed to > kernelorg for testing in zeroday. If it builds fine I will push it > to devel. > > Must say this series is impressive. It's doing away with a whole > slew of "technical debt" (old code not using modern frameworks). Yeah, I gave up twice while trying to untangle the mess in that driver. It had indeed a lot of technical debt accumulated over the years of incremental development. I'm worried this series breaks some of the chips though, as I couldn't test it on the whole lot of the supported ones. I even wonder whether we shouldn't remove support for some of the chips which have no users in the kernel and add extra complexity to the driver, like the PCA957x . > Strangely this driver doesn't support any pin config, it even seems > to have per-pin debounce and everything. That depends on the chip, really. Most of the PCA953x series and compatible only have the In/Out/Direction/Invert registers, in various quantities. There are some which have extra functionality (like the integrated pull resistors) but those are rare. > Some can be quickly > supported by just adding the .set_config() callback, others like > pull up/down are more dubious. If it supports open drain in hardware > we should definately make use of it. Just in case you're interested! I went through the hardware I have around and the datasheets to the PCA953x chips on them, but I couldn't find a board which would have a PCA953x chip with those extra features. I'll keep my eyes peeled for a board with one.
On Sat, Dec 15, 2018 at 5:48 AM Marek Vasut <marek.vasut@gmail.com> wrote: > On 12/14/2018 03:50 PM, Linus Walleij wrote: > > Some can be quickly > > supported by just adding the .set_config() callback, others like > > pull up/down are more dubious. If it supports open drain in hardware > > we should definately make use of it. Just in case you're interested! > > I went through the hardware I have around and the datasheets to the > PCA953x chips on them, but I couldn't find a board which would have a > PCA953x chip with those extra features. I'll keep my eyes peeled for a > board with one. It appears Thomas needs those features so let's let him have a go at it :D Yours, Linus Walleij
On 12/16/2018 01:27 AM, Linus Walleij wrote: > On Sat, Dec 15, 2018 at 5:48 AM Marek Vasut <marek.vasut@gmail.com> wrote: >> On 12/14/2018 03:50 PM, Linus Walleij wrote: > >>> Some can be quickly >>> supported by just adding the .set_config() callback, others like >>> pull up/down are more dubious. If it supports open drain in hardware >>> we should definately make use of it. Just in case you're interested! >> >> I went through the hardware I have around and the datasheets to the >> PCA953x chips on them, but I couldn't find a board which would have a >> PCA953x chip with those extra features. I'll keep my eyes peeled for a >> board with one. > > It appears Thomas needs those features so let's let him have a go > at it :D Awesome :-)
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index 540166443c34..afe6de4c48c4 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -159,11 +159,16 @@ struct pca953x_chip { int (*read_regs)(struct pca953x_chip *, int, u8 *); }; +static int pca953x_bank_shift(struct pca953x_chip *chip) +{ + return fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); +} + static int pca953x_read_single(struct pca953x_chip *chip, int reg, u32 *val, int off) { int ret; - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); + int bank_shift = pca953x_bank_shift(chip); int offset = off / BANK_SZ; ret = i2c_smbus_read_byte_data(chip->client, @@ -182,7 +187,7 @@ static int pca953x_write_single(struct pca953x_chip *chip, int reg, u32 val, int off) { int ret; - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); + int bank_shift = pca953x_bank_shift(chip); int offset = off / BANK_SZ; ret = i2c_smbus_write_byte_data(chip->client, @@ -221,7 +226,7 @@ static int pca957x_write_regs_16(struct pca953x_chip *chip, int reg, u8 *val) static int pca953x_write_regs_24(struct pca953x_chip *chip, int reg, u8 *val) { - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); + int bank_shift = pca953x_bank_shift(chip); int addr = (reg & PCAL_GPIO_MASK) << bank_shift; int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1; @@ -265,7 +270,7 @@ static int pca953x_read_regs_16(struct pca953x_chip *chip, int reg, u8 *val) static int pca953x_read_regs_24(struct pca953x_chip *chip, int reg, u8 *val) { - int bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); + int bank_shift = pca953x_bank_shift(chip); int addr = (reg & PCAL_GPIO_MASK) << bank_shift; int pinctrl = (reg & PCAL_PINCTRL_MASK) << 1; @@ -402,13 +407,12 @@ static void pca953x_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask, unsigned long *bits) { struct pca953x_chip *chip = gpiochip_get_data(gc); + int bank_shift = pca953x_bank_shift(chip); unsigned int bank_mask, bank_val; - int bank_shift, bank; + int bank; u8 reg_val[MAX_BANK]; int ret; - bank_shift = fls((chip->gpio_chip.ngpio - 1) / BANK_SZ); - mutex_lock(&chip->i2c_lock); memcpy(reg_val, chip->reg_output, NBANK(chip)); for (bank = 0; bank < NBANK(chip); bank++) {
The bank_shift = fls(...) code was duplicated in the driver 5 times, pull it into separate function. Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> --- V2: Replace bank_size with bank_shift in commit message --- drivers/gpio/gpio-pca953x.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-)