1 // SPDX-License-Identifier: GPL-2.0-or-later
13 #include <linux/gpio/consumer.h>
15 #include <linux/i2c-of-prober.h>
27  * resources, they can be marked as "fail-needs-probe" and have a prober
30  * This prober assumes such drop-in parts are on the same I2C bus, have
31  * non-conflicting addresses, and can be directly probed by seeing which
35  * - Support I2C muxes
68 		return -ENOMEM;  in i2c_of_probe_enable_node()
93  * i2c_of_probe_component() - probe for devices of "type" on the same i2c bus
95  * @cfg: Pointer to the &struct i2c_of_probe_cfg containing callbacks and other options
99  * Probe for possible I2C components of the same "type" (&i2c_of_probe_cfg->type)
100  * on the same I2C bus that have their status marked as "fail-needs-probe".
112  * Context: Process context only. Does non-atomic I2C transfers.
114  *          can return -EPROBE_DEFER if the I2C adapter or other resources
116  * Return: 0 on success or no-op, error code otherwise.
117  *         A no-op can happen when it seems like the device tree already
120  *         the status of the to-be-probed components as "fail-needs-probe".
127 int i2c_of_probe_component(struct device *dev, const struct i2c_of_probe_cfg *cfg, void *ctx)  in i2c_of_probe_component()  argument
134 	ops = cfg->ops ?: &i2c_of_probe_dummy_ops;  in i2c_of_probe_component()
135 	type = cfg->type;  in i2c_of_probe_component()
139 		return -ENODEV;  in i2c_of_probe_component()
142 	 * If any devices of the given "type" are already enabled then this function is a no-op.  in i2c_of_probe_component()
152 		return dev_err_probe(dev, -EPROBE_DEFER, "Couldn't get I2C adapter\n");  in i2c_of_probe_component()
156 	if (ops->enable)  in i2c_of_probe_component()
157 		ret = ops->enable(dev, i2c_node, ctx);  in i2c_of_probe_component()
171 		if (ops->cleanup_early)  in i2c_of_probe_component()
172 			ops->cleanup_early(dev, ctx);  in i2c_of_probe_component()
177 	if (ops->cleanup)  in i2c_of_probe_component()
178 		ops->cleanup(dev, ctx);  in i2c_of_probe_component()
198 	supply_name = ctx->opts->supply_name;  in i2c_of_probe_simple_get_supply()
209 	ctx->supply = supply;  in i2c_of_probe_simple_get_supply()
216 	regulator_put(ctx->supply);  in i2c_of_probe_simple_put_supply()
217 	ctx->supply = NULL;  in i2c_of_probe_simple_put_supply()
224 	if (!ctx->supply)  in i2c_of_probe_simple_enable_regulator()
227 	dev_dbg(dev, "Enabling regulator supply \"%s\"\n", ctx->opts->supply_name);  in i2c_of_probe_simple_enable_regulator()
229 	ret = regulator_enable(ctx->supply);  in i2c_of_probe_simple_enable_regulator()
233 	if (ctx->opts->post_power_on_delay_ms)  in i2c_of_probe_simple_enable_regulator()
234 		msleep(ctx->opts->post_power_on_delay_ms);  in i2c_of_probe_simple_enable_regulator()
241 	if (!ctx->supply)  in i2c_of_probe_simple_disable_regulator()
244 	dev_dbg(dev, "Disabling regulator supply \"%s\"\n", ctx->opts->supply_name);  in i2c_of_probe_simple_disable_regulator()
246 	regulator_disable(ctx->supply);  in i2c_of_probe_simple_disable_regulator()
256 	/* NULL signals no GPIO needed */  in i2c_of_probe_simple_get_gpiod()
257 	if (!ctx->opts->gpio_name)  in i2c_of_probe_simple_get_gpiod()
260 	/* An empty string signals an unnamed GPIO */  in i2c_of_probe_simple_get_gpiod()
261 	if (!ctx->opts->gpio_name[0])  in i2c_of_probe_simple_get_gpiod()
264 		con_id = ctx->opts->gpio_name;  in i2c_of_probe_simple_get_gpiod()
266 	gpiod = fwnode_gpiod_get_index(fwnode, con_id, 0, GPIOD_ASIS, "i2c-of-prober");  in i2c_of_probe_simple_get_gpiod()
270 	ctx->gpiod = gpiod;  in i2c_of_probe_simple_get_gpiod()
277 	gpiod_put(ctx->gpiod);  in i2c_of_probe_simple_put_gpiod()
278 	ctx->gpiod = NULL;  in i2c_of_probe_simple_put_gpiod()
285 	if (!ctx->gpiod)  in i2c_of_probe_simple_set_gpio()
288 	dev_dbg(dev, "Configuring GPIO\n");  in i2c_of_probe_simple_set_gpio()
290 	ret = gpiod_direction_output(ctx->gpiod, ctx->opts->gpio_assert_to_enable);  in i2c_of_probe_simple_set_gpio()
294 	if (ctx->opts->post_gpio_config_delay_ms)  in i2c_of_probe_simple_set_gpio()
295 		msleep(ctx->opts->post_gpio_config_delay_ms);  in i2c_of_probe_simple_set_gpio()
302 	gpiod_set_value(ctx->gpiod, !ctx->opts->gpio_assert_to_enable);  in i2c_of_probe_simple_disable_gpio()
306  * i2c_of_probe_simple_enable - Simple helper for I2C OF prober to get and enable resources
311  * If &i2c_of_probe_simple_opts->supply_name is given, request the named regulator supply.
312  * If &i2c_of_probe_simple_opts->gpio_name is given, request the named GPIO. Or if it is
313  * the empty string, request the unnamed GPIO.
315  * If a GPIO line was found, configure the GPIO line to output and set value
318  * Return: %0 on success or no-op, or a negative error number on failure.
329 	if (!ctx || !ctx->opts)  in i2c_of_probe_simple_enable()
330 		return -EINVAL;  in i2c_of_probe_simple_enable()
332 	compat = ctx->opts->res_node_compatible;  in i2c_of_probe_simple_enable()
334 		return -EINVAL;  in i2c_of_probe_simple_enable()
338 		return dev_err_probe(dev, -ENODEV, "No device compatible with \"%s\" found\n",  in i2c_of_probe_simple_enable()
372  * i2c_of_probe_simple_cleanup_early - \
377  * GPIO descriptors are exclusive and have to be released before the
389  * i2c_of_probe_simple_cleanup - Clean up and release resources for I2C OF prober simple helpers
393  * * If a GPIO line was found and not yet released, set its value to the opposite of that
401 	/* GPIO operations here are no-ops if i2c_of_probe_simple_cleanup_early was called. */  in i2c_of_probe_simple_cleanup()