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path: root/drivers/i2c/muxes/i2c-mux-gpio.c
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Diffstat (limited to 'drivers/i2c/muxes/i2c-mux-gpio.c')
-rw-r--r--drivers/i2c/muxes/i2c-mux-gpio.c73
1 files changed, 40 insertions, 33 deletions
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index b8e11c1..e5cf26e 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -15,11 +15,10 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/gpio.h>
+#include "../../gpio/gpiolib.h"
#include <linux/of_gpio.h>
struct gpiomux {
- struct i2c_adapter *parent;
- struct i2c_adapter **adap; /* child busses */
struct i2c_mux_gpio_platform_data data;
unsigned gpio_base;
};
@@ -33,18 +32,18 @@ static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
val & (1 << i));
}
-static int i2c_mux_gpio_select(struct i2c_adapter *adap, void *data, u32 chan)
+static int i2c_mux_gpio_select(struct i2c_mux_core *muxc, u32 chan)
{
- struct gpiomux *mux = data;
+ struct gpiomux *mux = i2c_mux_priv(muxc);
i2c_mux_gpio_set(mux, chan);
return 0;
}
-static int i2c_mux_gpio_deselect(struct i2c_adapter *adap, void *data, u32 chan)
+static int i2c_mux_gpio_deselect(struct i2c_mux_core *muxc, u32 chan)
{
- struct gpiomux *mux = data;
+ struct gpiomux *mux = i2c_mux_priv(muxc);
i2c_mux_gpio_set(mux, mux->data.idle);
@@ -136,19 +135,16 @@ static int i2c_mux_gpio_probe_dt(struct gpiomux *mux,
static int i2c_mux_gpio_probe(struct platform_device *pdev)
{
+ struct i2c_mux_core *muxc;
struct gpiomux *mux;
struct i2c_adapter *parent;
- int (*deselect) (struct i2c_adapter *, void *, u32);
+ struct i2c_adapter *root;
unsigned initial_state, gpio_base;
int i, ret;
mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL);
- if (!mux) {
- dev_err(&pdev->dev, "Cannot allocate gpiomux structure");
+ if (!mux)
return -ENOMEM;
- }
-
- platform_set_drvdata(pdev, mux);
if (!dev_get_platdata(&pdev->dev)) {
ret = i2c_mux_gpio_probe_dt(mux, pdev);
@@ -180,27 +176,32 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
if (!parent)
return -EPROBE_DEFER;
- mux->parent = parent;
- mux->gpio_base = gpio_base;
-
- mux->adap = devm_kzalloc(&pdev->dev,
- sizeof(*mux->adap) * mux->data.n_values,
- GFP_KERNEL);
- if (!mux->adap) {
- dev_err(&pdev->dev, "Cannot allocate i2c_adapter structure");
+ muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, 0, 0,
+ i2c_mux_gpio_select, NULL);
+ if (!muxc) {
ret = -ENOMEM;
goto alloc_failed;
}
+ muxc->priv = mux;
+
+ platform_set_drvdata(pdev, muxc);
+
+ root = i2c_root_adapter(&parent->dev);
+
+ muxc->mux_locked = true;
+ mux->gpio_base = gpio_base;
if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) {
initial_state = mux->data.idle;
- deselect = i2c_mux_gpio_deselect;
+ muxc->deselect = i2c_mux_gpio_deselect;
} else {
initial_state = mux->data.values[0];
- deselect = NULL;
}
for (i = 0; i < mux->data.n_gpios; i++) {
+ struct device *gpio_dev;
+ struct gpio_desc *gpio_desc;
+
ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio");
if (ret) {
dev_err(&pdev->dev, "Failed to request GPIO %d\n",
@@ -217,17 +218,24 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
i++; /* gpio_request above succeeded, so must free */
goto err_request_gpio;
}
+
+ 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;
}
+ if (muxc->mux_locked)
+ dev_info(&pdev->dev, "mux-locked i2c mux\n");
+
for (i = 0; i < mux->data.n_values; i++) {
u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0;
unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
- mux->adap[i] = i2c_add_mux_adapter(parent, &pdev->dev, mux, nr,
- mux->data.values[i], class,
- i2c_mux_gpio_select, deselect);
- if (!mux->adap[i]) {
- ret = -ENODEV;
+ ret = i2c_mux_add_adapter(muxc, nr, mux->data.values[i], class);
+ if (ret) {
dev_err(&pdev->dev, "Failed to add adapter %d\n", i);
goto add_adapter_failed;
}
@@ -239,8 +247,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
return 0;
add_adapter_failed:
- for (; i > 0; i--)
- i2c_del_mux_adapter(mux->adap[i - 1]);
+ i2c_mux_del_adapters(muxc);
i = mux->data.n_gpios;
err_request_gpio:
for (; i > 0; i--)
@@ -253,16 +260,16 @@ alloc_failed:
static int i2c_mux_gpio_remove(struct platform_device *pdev)
{
- struct gpiomux *mux = platform_get_drvdata(pdev);
+ struct i2c_mux_core *muxc = platform_get_drvdata(pdev);
+ struct gpiomux *mux = i2c_mux_priv(muxc);
int i;
- for (i = 0; i < mux->data.n_values; i++)
- i2c_del_mux_adapter(mux->adap[i]);
+ i2c_mux_del_adapters(muxc);
for (i = 0; i < mux->data.n_gpios; i++)
gpio_free(mux->gpio_base + mux->data.gpios[i]);
- i2c_put_adapter(mux->parent);
+ i2c_put_adapter(muxc->parent);
return 0;
}