1 /*
2 * drivers/mmc/host/sdhci-spear.c
3 *
4 * Support of SDHCI platform devices for spear soc family
5 *
6 * Copyright (C) 2010 ST Microelectronics
7 * Viresh Kumar <vireshk@kernel.org>
8 *
9 * Inspired by sdhci-pltfm.c
10 *
11 * This file is licensed under the terms of the GNU General Public
12 * License version 2. This program is licensed "as is" without any
13 * warranty of any kind, whether express or implied.
14 */
15
16 #include <linux/clk.h>
17 #include <linux/delay.h>
18 #include <linux/gpio.h>
19 #include <linux/highmem.h>
20 #include <linux/module.h>
21 #include <linux/interrupt.h>
22 #include <linux/irq.h>
23 #include <linux/of.h>
24 #include <linux/of_gpio.h>
25 #include <linux/platform_device.h>
26 #include <linux/pm.h>
27 #include <linux/slab.h>
28 #include <linux/mmc/host.h>
29 #include <linux/mmc/slot-gpio.h>
30 #include <linux/io.h>
31 #include "sdhci.h"
32
33 struct spear_sdhci {
34 struct clk *clk;
35 int card_int_gpio;
36 };
37
38 /* sdhci ops */
39 static const struct sdhci_ops sdhci_pltfm_ops = {
40 .set_clock = sdhci_set_clock,
41 .set_bus_width = sdhci_set_bus_width,
42 .reset = sdhci_reset,
43 .set_uhs_signaling = sdhci_set_uhs_signaling,
44 };
45
sdhci_probe_config_dt(struct device_node * np,struct spear_sdhci * host)46 static void sdhci_probe_config_dt(struct device_node *np,
47 struct spear_sdhci *host)
48 {
49 int cd_gpio;
50
51 cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
52 if (!gpio_is_valid(cd_gpio))
53 cd_gpio = -1;
54
55 host->card_int_gpio = cd_gpio;
56 }
57
sdhci_probe(struct platform_device * pdev)58 static int sdhci_probe(struct platform_device *pdev)
59 {
60 struct sdhci_host *host;
61 struct resource *iomem;
62 struct spear_sdhci *sdhci;
63 struct device *dev;
64 int ret;
65
66 dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev;
67 host = sdhci_alloc_host(dev, sizeof(*sdhci));
68 if (IS_ERR(host)) {
69 ret = PTR_ERR(host);
70 dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
71 goto err;
72 }
73
74 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
75 host->ioaddr = devm_ioremap_resource(&pdev->dev, iomem);
76 if (IS_ERR(host->ioaddr)) {
77 ret = PTR_ERR(host->ioaddr);
78 dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret);
79 goto err_host;
80 }
81
82 host->hw_name = "sdhci";
83 host->ops = &sdhci_pltfm_ops;
84 host->irq = platform_get_irq(pdev, 0);
85 if (host->irq <= 0) {
86 ret = -EINVAL;
87 goto err_host;
88 }
89 host->quirks = SDHCI_QUIRK_BROKEN_ADMA;
90
91 sdhci = sdhci_priv(host);
92
93 /* clk enable */
94 sdhci->clk = devm_clk_get(&pdev->dev, NULL);
95 if (IS_ERR(sdhci->clk)) {
96 ret = PTR_ERR(sdhci->clk);
97 dev_dbg(&pdev->dev, "Error getting clock\n");
98 goto err_host;
99 }
100
101 ret = clk_prepare_enable(sdhci->clk);
102 if (ret) {
103 dev_dbg(&pdev->dev, "Error enabling clock\n");
104 goto err_host;
105 }
106
107 ret = clk_set_rate(sdhci->clk, 50000000);
108 if (ret)
109 dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",
110 clk_get_rate(sdhci->clk));
111
112 sdhci_probe_config_dt(pdev->dev.of_node, sdhci);
113 /*
114 * It is optional to use GPIOs for sdhci card detection. If
115 * sdhci->card_int_gpio < 0, then use original sdhci lines otherwise
116 * GPIO lines. We use the built-in GPIO support for this.
117 */
118 if (sdhci->card_int_gpio >= 0) {
119 ret = mmc_gpio_request_cd(host->mmc, sdhci->card_int_gpio, 0);
120 if (ret < 0) {
121 dev_dbg(&pdev->dev,
122 "failed to request card-detect gpio%d\n",
123 sdhci->card_int_gpio);
124 goto disable_clk;
125 }
126 }
127
128 ret = sdhci_add_host(host);
129 if (ret)
130 goto disable_clk;
131
132 platform_set_drvdata(pdev, host);
133
134 return 0;
135
136 disable_clk:
137 clk_disable_unprepare(sdhci->clk);
138 err_host:
139 sdhci_free_host(host);
140 err:
141 dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
142 return ret;
143 }
144
sdhci_remove(struct platform_device * pdev)145 static int sdhci_remove(struct platform_device *pdev)
146 {
147 struct sdhci_host *host = platform_get_drvdata(pdev);
148 struct spear_sdhci *sdhci = sdhci_priv(host);
149 int dead = 0;
150 u32 scratch;
151
152 scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
153 if (scratch == (u32)-1)
154 dead = 1;
155
156 sdhci_remove_host(host, dead);
157 clk_disable_unprepare(sdhci->clk);
158 sdhci_free_host(host);
159
160 return 0;
161 }
162
163 #ifdef CONFIG_PM_SLEEP
sdhci_suspend(struct device * dev)164 static int sdhci_suspend(struct device *dev)
165 {
166 struct sdhci_host *host = dev_get_drvdata(dev);
167 struct spear_sdhci *sdhci = sdhci_priv(host);
168 int ret;
169
170 if (host->tuning_mode != SDHCI_TUNING_MODE_3)
171 mmc_retune_needed(host->mmc);
172
173 ret = sdhci_suspend_host(host);
174 if (!ret)
175 clk_disable(sdhci->clk);
176
177 return ret;
178 }
179
sdhci_resume(struct device * dev)180 static int sdhci_resume(struct device *dev)
181 {
182 struct sdhci_host *host = dev_get_drvdata(dev);
183 struct spear_sdhci *sdhci = sdhci_priv(host);
184 int ret;
185
186 ret = clk_enable(sdhci->clk);
187 if (ret) {
188 dev_dbg(dev, "Resume: Error enabling clock\n");
189 return ret;
190 }
191
192 return sdhci_resume_host(host);
193 }
194 #endif
195
196 static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume);
197
198 #ifdef CONFIG_OF
199 static const struct of_device_id sdhci_spear_id_table[] = {
200 { .compatible = "st,spear300-sdhci" },
201 {}
202 };
203 MODULE_DEVICE_TABLE(of, sdhci_spear_id_table);
204 #endif
205
206 static struct platform_driver sdhci_driver = {
207 .driver = {
208 .name = "sdhci",
209 .pm = &sdhci_pm_ops,
210 .of_match_table = of_match_ptr(sdhci_spear_id_table),
211 },
212 .probe = sdhci_probe,
213 .remove = sdhci_remove,
214 };
215
216 module_platform_driver(sdhci_driver);
217
218 MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
219 MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");
220 MODULE_LICENSE("GPL v2");
221
