1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2021 SAMSUNG Electronics
4  * Jaehoon Chung <jh80.chung@samsung.com>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <mmc.h>
10 #include <pwrseq.h>
11 #include <asm/gpio.h>
12 #include <linux/delay.h>
13 
mmc_pwrseq_get_power(struct udevice * dev,struct mmc_config * cfg)14 int mmc_pwrseq_get_power(struct udevice *dev, struct mmc_config *cfg)
15 {
16 	/* Enable power if needed */
17 	return uclass_get_device_by_phandle(UCLASS_PWRSEQ, dev, "mmc-pwrseq",
18 					   &cfg->pwr_dev);
19 }
20 
mmc_pwrseq_set_power(struct udevice * dev,bool enable)21 static int mmc_pwrseq_set_power(struct udevice *dev, bool enable)
22 {
23 	struct gpio_desc reset;
24 	int ret;
25 
26 	ret = gpio_request_by_name(dev, "reset-gpios", 0, &reset, GPIOD_IS_OUT);
27 	if (ret)
28 		return ret;
29 	dm_gpio_set_value(&reset, 1);
30 	udelay(1);
31 	dm_gpio_set_value(&reset, 0);
32 	udelay(200);
33 
34 	return 0;
35 }
36 
37 static const struct pwrseq_ops mmc_pwrseq_ops = {
38 	.set_power	= mmc_pwrseq_set_power,
39 };
40 
41 static const struct udevice_id mmc_pwrseq_ids[] = {
42 	{ .compatible = "mmc-pwrseq-emmc" },
43 	{ }
44 };
45 
46 U_BOOT_DRIVER(mmc_pwrseq_drv) = {
47 	.name		= "mmc_pwrseq_emmc",
48 	.id		= UCLASS_PWRSEQ,
49 	.of_match	= mmc_pwrseq_ids,
50 	.ops		= &mmc_pwrseq_ops,
51 };
52