| Message ID | 20130616234152.23721.85467.sendpatchset@w520 (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Mon, Jun 17, 2013 at 1:41 AM, Magnus Damm <magnus.damm@gmail.com> wrote: > From: Magnus Damm <damm@opensource.se> > > Testing on r8a7790 shows that INDT does not indicate the correct > pin state when reading a GPIO configured as output, so update > the gpio_rcar_get() function to handle this case. > > Signed-off-by: Magnus Damm <damm@opensource.se> Patch applied. Unless you need this to go through some SH tree, I'm carrying it in the GPIO tree. Yours, Linus Walleij -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Linus, On Mon, Jun 17, 2013 at 5:35 PM, Linus Walleij <linus.walleij@linaro.org> wrote: > On Mon, Jun 17, 2013 at 1:41 AM, Magnus Damm <magnus.damm@gmail.com> wrote: > >> From: Magnus Damm <damm@opensource.se> >> >> Testing on r8a7790 shows that INDT does not indicate the correct >> pin state when reading a GPIO configured as output, so update >> the gpio_rcar_get() function to handle this case. >> >> Signed-off-by: Magnus Damm <damm@opensource.se> > > Patch applied. Unless you need this to go through some SH > tree, I'm carrying it in the GPIO tree. Thanks a lot! You carrying it in the GPIO tree sounds perfect to me. Cheers, / magnus -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Magnus, On Monday 17 June 2013 08:41:52 Magnus Damm wrote: > From: Magnus Damm <damm@opensource.se> > > Testing on r8a7790 shows that INDT does not indicate the correct > pin state when reading a GPIO configured as output, so update > the gpio_rcar_get() function to handle this case. Have you checked whether this is true on the other SoCs as well ? Reading back the output register instead of the input register will not allow detection of conflicts. If the hardware can't provide that, fine, but otherwise it would be a nice feature to keep (although it might not get used in practice). > Signed-off-by: Magnus Damm <damm@opensource.se> Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > > drivers/gpio/gpio-rcar.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > --- 0001/drivers/gpio/gpio-rcar.c > +++ work/drivers/gpio/gpio-rcar.c 2013-06-12 09:23:53.000000000 +0900 > @@ -230,7 +230,14 @@ static int gpio_rcar_direction_input(str > > static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset) > { > - return (int)(gpio_rcar_read(gpio_to_priv(chip), INDT) & BIT(offset)); > + u32 bit = BIT(offset); > + > + /* testing on r8a7790 shows that INDT does not show correct pin state > + * when configured as output, so use OUTDT in case of output pins */ > + if (gpio_rcar_read(gpio_to_priv(chip), INOUTSEL) & bit) > + return (int)(gpio_rcar_read(gpio_to_priv(chip), OUTDT) & bit); > + else > + return (int)(gpio_rcar_read(gpio_to_priv(chip), INDT) & bit); > } > > static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int > value)
Hi Laurent, On Mon, Jun 17, 2013 at 7:58 PM, Laurent Pinchart <laurent.pinchart@ideasonboard.com> wrote: > Hi Magnus, > > On Monday 17 June 2013 08:41:52 Magnus Damm wrote: >> From: Magnus Damm <damm@opensource.se> >> >> Testing on r8a7790 shows that INDT does not indicate the correct >> pin state when reading a GPIO configured as output, so update >> the gpio_rcar_get() function to handle this case. > > Have you checked whether this is true on the other SoCs as well ? Reading back > the output register instead of the input register will not allow detection of > conflicts. If the hardware can't provide that, fine, but otherwise it would be > a nice feature to keep (although it might not get used in practice). I have not tested this patch myself, but I've received feedback from an internal team at Renesas. Regarding other SoCs, I'm quite confident in this change, the data sheet for both R-Car H2 and R-Car H1 have the following sentence in them: "INDT is valid only for the ports for which general input/output mode is selected by the general IO/interrupt switching register and then general input mode is selected by the general input/output switching register" I agree it would be nice with hardware that allowed reading the pin state regardless independently of any mode setting. =) >> Signed-off-by: Magnus Damm <damm@opensource.se> > > Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Thanks! / magnus -- To unsubscribe from this list: send the line "unsubscribe linux-sh" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
--- 0001/drivers/gpio/gpio-rcar.c +++ work/drivers/gpio/gpio-rcar.c 2013-06-12 09:23:53.000000000 +0900 @@ -230,7 +230,14 @@ static int gpio_rcar_direction_input(str static int gpio_rcar_get(struct gpio_chip *chip, unsigned offset) { - return (int)(gpio_rcar_read(gpio_to_priv(chip), INDT) & BIT(offset)); + u32 bit = BIT(offset); + + /* testing on r8a7790 shows that INDT does not show correct pin state + * when configured as output, so use OUTDT in case of output pins */ + if (gpio_rcar_read(gpio_to_priv(chip), INOUTSEL) & bit) + return (int)(gpio_rcar_read(gpio_to_priv(chip), OUTDT) & bit); + else + return (int)(gpio_rcar_read(gpio_to_priv(chip), INDT) & bit); } static void gpio_rcar_set(struct gpio_chip *chip, unsigned offset, int value)