2016-11-24 21:53:52

by Peter Rosin

[permalink] [raw]
Subject: [PATCH v3] i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep

If the gpio controller supports it and the gpio lines are concentrated
to one gpio chip, the mux controller pins will get updated simultaneously.

Signed-off-by: Peter Rosin <[email protected]>
---
drivers/i2c/muxes/i2c-mux-gpio.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

Hi!

v2 -> v3 changes
- preallocate temporary storage for the values array needed by the
gpiod_set_array_value_cansleep call, killing a warning about variable
length arrays reported by Wolfram.
- allocate a correctly sized array for gpios (number of pins, not
number of channels).

v1 -> v2 changes
- rebase onto something without interference from other patches

Cheers,
Peter

diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index e5cf26eefa97..655684d621a4 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -21,6 +21,8 @@
struct gpiomux {
struct i2c_mux_gpio_platform_data data;
unsigned gpio_base;
+ struct gpio_desc **gpios;
+ int *values;
};

static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
@@ -28,8 +30,10 @@ static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
int i;

for (i = 0; i < mux->data.n_gpios; i++)
- gpio_set_value_cansleep(mux->gpio_base + mux->data.gpios[i],
- val & (1 << i));
+ mux->values[i] = (val >> i) & 1;
+
+ gpiod_set_array_value_cansleep(mux->data.n_gpios,
+ mux->gpios, mux->values);
}

static int i2c_mux_gpio_select(struct i2c_mux_core *muxc, u32 chan)
@@ -176,12 +180,16 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
if (!parent)
return -EPROBE_DEFER;

- muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, 0, 0,
+ muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values,
+ mux->data.n_gpios * sizeof(*mux->gpios) +
+ mux->data.n_gpios * sizeof(*mux->values), 0,
i2c_mux_gpio_select, NULL);
if (!muxc) {
ret = -ENOMEM;
goto alloc_failed;
}
+ mux->gpios = muxc->priv;
+ mux->values = (int *)(mux->gpios + mux->data.n_gpios);
muxc->priv = mux;

platform_set_drvdata(pdev, muxc);
@@ -219,10 +227,12 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
goto err_request_gpio;
}

+ gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
+ mux->gpios[i] = gpio_desc;
+
if (!muxc->mux_locked)
continue;

- gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]);
gpio_dev = &gpio_desc->gdev->dev;
muxc->mux_locked = i2c_root_adapter(gpio_dev) == root;
}
--
2.1.4


2016-11-29 19:15:23

by Wolfram Sang

[permalink] [raw]
Subject: Re: [PATCH v3] i2c: i2c-mux-gpio: update mux with gpiod_set_array_value_cansleep

On Thu, Nov 24, 2016 at 07:19:28PM +0100, Peter Rosin wrote:
> If the gpio controller supports it and the gpio lines are concentrated
> to one gpio chip, the mux controller pins will get updated simultaneously.
>
> Signed-off-by: Peter Rosin <[email protected]>

Applied to for-next, thanks!


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