1 /* 2 * Copyright (C) 2014 Linaro Ltd 3 * 4 * Author: Ulf Hansson <ulf.hansson@linaro.org> 5 * 6 * License terms: GNU General Public License (GPL) version 2 7 * 8 * MMC power sequence management 9 */ 10 #include <linux/kernel.h> 11 #include <linux/platform_device.h> 12 #include <linux/err.h> 13 #include <linux/of.h> 14 #include <linux/of_platform.h> 15 16 #include <linux/mmc/host.h> 17 18 #include "pwrseq.h" 19 20 struct mmc_pwrseq_match { 21 const char *compatible; 22 struct mmc_pwrseq *(*alloc)(struct mmc_host *host, struct device *dev); 23 }; 24 25 static struct mmc_pwrseq_match pwrseq_match[] = { 26 { 27 .compatible = "mmc-pwrseq-simple", 28 .alloc = mmc_pwrseq_simple_alloc, 29 }, { 30 .compatible = "mmc-pwrseq-emmc", 31 .alloc = mmc_pwrseq_emmc_alloc, 32 }, 33 }; 34 35 static struct mmc_pwrseq_match *mmc_pwrseq_find(struct device_node *np) 36 { 37 struct mmc_pwrseq_match *match = ERR_PTR(-ENODEV); 38 int i; 39 40 for (i = 0; i < ARRAY_SIZE(pwrseq_match); i++) { 41 if (of_device_is_compatible(np, pwrseq_match[i].compatible)) { 42 match = &pwrseq_match[i]; 43 break; 44 } 45 } 46 47 return match; 48 } 49 50 int mmc_pwrseq_alloc(struct mmc_host *host) 51 { 52 struct platform_device *pdev; 53 struct device_node *np; 54 struct mmc_pwrseq_match *match; 55 struct mmc_pwrseq *pwrseq; 56 int ret = 0; 57 58 np = of_parse_phandle(host->parent->of_node, "mmc-pwrseq", 0); 59 if (!np) 60 return 0; 61 62 pdev = of_find_device_by_node(np); 63 if (!pdev) { 64 ret = -ENODEV; 65 goto err; 66 } 67 68 match = mmc_pwrseq_find(np); 69 if (IS_ERR(match)) { 70 ret = PTR_ERR(match); 71 goto err; 72 } 73 74 pwrseq = match->alloc(host, &pdev->dev); 75 if (IS_ERR(pwrseq)) { 76 ret = PTR_ERR(pwrseq); 77 goto err; 78 } 79 80 host->pwrseq = pwrseq; 81 dev_info(host->parent, "allocated mmc-pwrseq\n"); 82 83 err: 84 of_node_put(np); 85 return ret; 86 } 87 88 void mmc_pwrseq_pre_power_on(struct mmc_host *host) 89 { 90 struct mmc_pwrseq *pwrseq = host->pwrseq; 91 92 if (pwrseq && pwrseq->ops && pwrseq->ops->pre_power_on) 93 pwrseq->ops->pre_power_on(host); 94 } 95 96 void mmc_pwrseq_post_power_on(struct mmc_host *host) 97 { 98 struct mmc_pwrseq *pwrseq = host->pwrseq; 99 100 if (pwrseq && pwrseq->ops && pwrseq->ops->post_power_on) 101 pwrseq->ops->post_power_on(host); 102 } 103 104 void mmc_pwrseq_power_off(struct mmc_host *host) 105 { 106 struct mmc_pwrseq *pwrseq = host->pwrseq; 107 108 if (pwrseq && pwrseq->ops && pwrseq->ops->power_off) 109 pwrseq->ops->power_off(host); 110 } 111 112 void mmc_pwrseq_free(struct mmc_host *host) 113 { 114 struct mmc_pwrseq *pwrseq = host->pwrseq; 115 116 if (pwrseq && pwrseq->ops && pwrseq->ops->free) 117 pwrseq->ops->free(host); 118 119 host->pwrseq = NULL; 120 } 121