Lines Matching +full:i2c +full:- +full:mux
2 * I2C multiplexer using GPIO API
11 #include <linux/i2c.h>
12 #include <linux/i2c-mux.h>
13 #include <linux/platform_data/i2c-mux-gpio.h>
28 static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val) in i2c_mux_gpio_set() argument
32 for (i = 0; i < mux->data.n_gpios; i++) in i2c_mux_gpio_set()
33 mux->values[i] = (val >> i) & 1; in i2c_mux_gpio_set()
35 gpiod_set_array_value_cansleep(mux->data.n_gpios, in i2c_mux_gpio_set()
36 mux->gpios, mux->values); in i2c_mux_gpio_set()
41 struct gpiomux *mux = i2c_mux_priv(muxc); in i2c_mux_gpio_select() local
43 i2c_mux_gpio_set(mux, chan); in i2c_mux_gpio_select()
50 struct gpiomux *mux = i2c_mux_priv(muxc); in i2c_mux_gpio_deselect() local
52 i2c_mux_gpio_set(mux, mux->data.idle); in i2c_mux_gpio_deselect()
60 return !strcmp(chip->label, data); in match_gpio_chip_by_label()
64 static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, in i2c_mux_gpio_probe_dt() argument
67 struct device_node *np = pdev->dev.of_node; in i2c_mux_gpio_probe_dt()
74 return -ENODEV; in i2c_mux_gpio_probe_dt()
76 adapter_np = of_parse_phandle(np, "i2c-parent", 0); in i2c_mux_gpio_probe_dt()
78 dev_err(&pdev->dev, "Cannot parse i2c-parent\n"); in i2c_mux_gpio_probe_dt()
79 return -ENODEV; in i2c_mux_gpio_probe_dt()
84 return -EPROBE_DEFER; in i2c_mux_gpio_probe_dt()
86 mux->data.parent = i2c_adapter_id(adapter); in i2c_mux_gpio_probe_dt()
87 put_device(&adapter->dev); in i2c_mux_gpio_probe_dt()
89 mux->data.n_values = of_get_child_count(np); in i2c_mux_gpio_probe_dt()
91 values = devm_kcalloc(&pdev->dev, in i2c_mux_gpio_probe_dt()
92 mux->data.n_values, sizeof(*mux->data.values), in i2c_mux_gpio_probe_dt()
95 dev_err(&pdev->dev, "Cannot allocate values array"); in i2c_mux_gpio_probe_dt()
96 return -ENOMEM; in i2c_mux_gpio_probe_dt()
103 mux->data.values = values; in i2c_mux_gpio_probe_dt()
105 if (of_property_read_u32(np, "idle-state", &mux->data.idle)) in i2c_mux_gpio_probe_dt()
106 mux->data.idle = I2C_MUX_GPIO_NO_IDLE; in i2c_mux_gpio_probe_dt()
108 mux->data.n_gpios = of_gpio_named_count(np, "mux-gpios"); in i2c_mux_gpio_probe_dt()
109 if (mux->data.n_gpios < 0) { in i2c_mux_gpio_probe_dt()
110 dev_err(&pdev->dev, "Missing mux-gpios property in the DT.\n"); in i2c_mux_gpio_probe_dt()
111 return -EINVAL; in i2c_mux_gpio_probe_dt()
114 gpios = devm_kcalloc(&pdev->dev, in i2c_mux_gpio_probe_dt()
115 mux->data.n_gpios, sizeof(*mux->data.gpios), in i2c_mux_gpio_probe_dt()
118 dev_err(&pdev->dev, "Cannot allocate gpios array"); in i2c_mux_gpio_probe_dt()
119 return -ENOMEM; in i2c_mux_gpio_probe_dt()
122 for (i = 0; i < mux->data.n_gpios; i++) { in i2c_mux_gpio_probe_dt()
123 ret = of_get_named_gpio(np, "mux-gpios", i); in i2c_mux_gpio_probe_dt()
129 mux->data.gpios = gpios; in i2c_mux_gpio_probe_dt()
134 static int i2c_mux_gpio_probe_dt(struct gpiomux *mux, in i2c_mux_gpio_probe_dt() argument
144 struct gpiomux *mux; in i2c_mux_gpio_probe() local
150 mux = devm_kzalloc(&pdev->dev, sizeof(*mux), GFP_KERNEL); in i2c_mux_gpio_probe()
151 if (!mux) in i2c_mux_gpio_probe()
152 return -ENOMEM; in i2c_mux_gpio_probe()
154 if (!dev_get_platdata(&pdev->dev)) { in i2c_mux_gpio_probe()
155 ret = i2c_mux_gpio_probe_dt(mux, pdev); in i2c_mux_gpio_probe()
159 memcpy(&mux->data, dev_get_platdata(&pdev->dev), in i2c_mux_gpio_probe()
160 sizeof(mux->data)); in i2c_mux_gpio_probe()
167 if (mux->data.gpio_chip) { in i2c_mux_gpio_probe()
170 gpio = gpiochip_find(mux->data.gpio_chip, in i2c_mux_gpio_probe()
173 return -EPROBE_DEFER; in i2c_mux_gpio_probe()
175 gpio_base = gpio->base; in i2c_mux_gpio_probe()
180 parent = i2c_get_adapter(mux->data.parent); in i2c_mux_gpio_probe()
182 return -EPROBE_DEFER; in i2c_mux_gpio_probe()
184 muxc = i2c_mux_alloc(parent, &pdev->dev, mux->data.n_values, in i2c_mux_gpio_probe()
185 mux->data.n_gpios * sizeof(*mux->gpios) + in i2c_mux_gpio_probe()
186 mux->data.n_gpios * sizeof(*mux->values), 0, in i2c_mux_gpio_probe()
189 ret = -ENOMEM; in i2c_mux_gpio_probe()
192 mux->gpios = muxc->priv; in i2c_mux_gpio_probe()
193 mux->values = (int *)(mux->gpios + mux->data.n_gpios); in i2c_mux_gpio_probe()
194 muxc->priv = mux; in i2c_mux_gpio_probe()
198 root = i2c_root_adapter(&parent->dev); in i2c_mux_gpio_probe()
200 muxc->mux_locked = true; in i2c_mux_gpio_probe()
201 mux->gpio_base = gpio_base; in i2c_mux_gpio_probe()
203 if (mux->data.idle != I2C_MUX_GPIO_NO_IDLE) { in i2c_mux_gpio_probe()
204 initial_state = mux->data.idle; in i2c_mux_gpio_probe()
205 muxc->deselect = i2c_mux_gpio_deselect; in i2c_mux_gpio_probe()
207 initial_state = mux->data.values[0]; in i2c_mux_gpio_probe()
210 for (i = 0; i < mux->data.n_gpios; i++) { in i2c_mux_gpio_probe()
214 ret = gpio_request(gpio_base + mux->data.gpios[i], "i2c-mux-gpio"); in i2c_mux_gpio_probe()
216 dev_err(&pdev->dev, "Failed to request GPIO %d\n", in i2c_mux_gpio_probe()
217 mux->data.gpios[i]); in i2c_mux_gpio_probe()
221 ret = gpio_direction_output(gpio_base + mux->data.gpios[i], in i2c_mux_gpio_probe()
224 dev_err(&pdev->dev, in i2c_mux_gpio_probe()
226 mux->data.gpios[i]); in i2c_mux_gpio_probe()
231 gpio_desc = gpio_to_desc(gpio_base + mux->data.gpios[i]); in i2c_mux_gpio_probe()
232 mux->gpios[i] = gpio_desc; in i2c_mux_gpio_probe()
234 if (!muxc->mux_locked) in i2c_mux_gpio_probe()
237 gpio_dev = &gpio_desc->gdev->dev; in i2c_mux_gpio_probe()
238 muxc->mux_locked = i2c_root_adapter(gpio_dev) == root; in i2c_mux_gpio_probe()
241 if (muxc->mux_locked) in i2c_mux_gpio_probe()
242 dev_info(&pdev->dev, "mux-locked i2c mux\n"); in i2c_mux_gpio_probe()
244 for (i = 0; i < mux->data.n_values; i++) { in i2c_mux_gpio_probe()
245 u32 nr = mux->data.base_nr ? (mux->data.base_nr + i) : 0; in i2c_mux_gpio_probe()
246 unsigned int class = mux->data.classes ? mux->data.classes[i] : 0; in i2c_mux_gpio_probe()
248 ret = i2c_mux_add_adapter(muxc, nr, mux->data.values[i], class); in i2c_mux_gpio_probe()
253 dev_info(&pdev->dev, "%d port mux on %s adapter\n", in i2c_mux_gpio_probe()
254 mux->data.n_values, parent->name); in i2c_mux_gpio_probe()
260 i = mux->data.n_gpios; in i2c_mux_gpio_probe()
262 for (; i > 0; i--) in i2c_mux_gpio_probe()
263 gpio_free(gpio_base + mux->data.gpios[i - 1]); in i2c_mux_gpio_probe()
273 struct gpiomux *mux = i2c_mux_priv(muxc); in i2c_mux_gpio_remove() local
278 for (i = 0; i < mux->data.n_gpios; i++) in i2c_mux_gpio_remove()
279 gpio_free(mux->gpio_base + mux->data.gpios[i]); in i2c_mux_gpio_remove()
281 i2c_put_adapter(muxc->parent); in i2c_mux_gpio_remove()
287 { .compatible = "i2c-mux-gpio", },
296 .name = "i2c-mux-gpio",
303 MODULE_DESCRIPTION("GPIO-based I2C multiplexer driver");
306 MODULE_ALIAS("platform:i2c-mux-gpio");