Re: [PATCH V2 5/5] gpio/gpio-stmpe: ADD support for stmpe variant 801
From: Rabin Vincent
Date: Fri Nov 18 2011 - 06:59:56 EST
On Thu, Nov 17, 2011 at 11:02, Viresh Kumar <viresh.kumar@xxxxxx> wrote:
> diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
> index 4c980b5..000b019 100644
> --- a/drivers/gpio/gpio-stmpe.c
> +++ b/drivers/gpio/gpio-stmpe.c
> @@ -65,7 +65,15 @@ static void stmpe_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
> u8 reg = stmpe->regs[which] - (offset / 8);
> u8 mask = 1 << (offset % 8);
>
> - stmpe_reg_write(stmpe, reg, mask);
> + /*
> + * Some variants have single register for gpio set/clear functionality.
> + * For them we need to write 0 to clear and 1 to set.
> + */
> + if (!val && (stmpe->regs[STMPE_IDX_GPSR_LSB] ==
> + stmpe->regs[STMPE_IDX_GPCR_LSB]))
> + stmpe_set_bits(stmpe, reg, mask, ~mask);
> + else
> + stmpe_set_bits(stmpe, reg, mask, mask);
> }
This code,
(1) for 801, when clearing one GPIO, sets all the others.
(2) for other devices, adds an an unnecessary read (within stmpe_set_bits()),
which wasn't there before.
Please rework to something like:
if (stmpe->regs[...)
stmpe_set_bits(stmpe, reg, mask, val ? mask : 0);
else
stmpe_reg_write(stmpe, reg, mask);
>
> static int stmpe_gpio_direction_output(struct gpio_chip *chip,
> @@ -125,10 +133,19 @@ static struct gpio_chip template_chip = {
> static int stmpe_gpio_irq_set_type(struct irq_data *d, unsigned int type)
> {
> struct stmpe_gpio *stmpe_gpio = irq_data_get_irq_chip_data(d);
> + struct stmpe *stmpe = stmpe_gpio->stmpe;
> int offset = d->irq - stmpe_gpio->irq_base;
> int regoffset = offset / 8;
> int mask = 1 << (offset % 8);
>
> + /* STMPE801 doesn't have RE and FE registers */
> + if (stmpe->partnum == STMPE801) {
> + if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH)
> + return 0;
This looks wrong. From the datasheet I see that it supports edges only,
so perhaps you meant to say IRQ_TYPE_EDGE_* above.
In that case please reorganize this to add the return 0 after the
existing check which excludes levels (below).
> + else
> + return -EINVAL;
> + }
> +
> if (type == IRQ_TYPE_LEVEL_LOW || type == IRQ_TYPE_LEVEL_HIGH)
> return -EINVAL;
--
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