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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.c18
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index f6270ee934f9..e5cf26eefa97 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -15,6 +15,7 @@
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/gpio.h>
+#include "../../gpio/gpiolib.h"
#include <linux/of_gpio.h>
struct gpiomux {
@@ -137,6 +138,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
struct i2c_mux_core *muxc;
struct gpiomux *mux;
struct i2c_adapter *parent;
+ struct i2c_adapter *root;
unsigned initial_state, gpio_base;
int i, ret;
@@ -184,6 +186,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
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) {
@@ -194,6 +199,9 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
}
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",
@@ -210,8 +218,18 @@ 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;