tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/highmem.h>
19#include <linux/module.h>
20#include <linux/interrupt.h>
21#include <linux/irq.h>
22#include <linux/of.h>
23#include <linux/platform_device.h>
24#include <linux/pm.h>
25#include <linux/slab.h>
26#include <linux/mmc/host.h>
27#include <linux/mmc/slot-gpio.h>
28#include <linux/io.h>
29#include "sdhci.h"
30
31struct spear_sdhci {
32 struct clk *clk;
33};
34
35/* sdhci ops */
36static const struct sdhci_ops sdhci_pltfm_ops = {
37 .set_clock = sdhci_set_clock,
38 .set_bus_width = sdhci_set_bus_width,
39 .reset = sdhci_reset,
40 .set_uhs_signaling = sdhci_set_uhs_signaling,
41};
42
43static int sdhci_probe(struct platform_device *pdev)
44{
45 struct sdhci_host *host;
46 struct resource *iomem;
47 struct spear_sdhci *sdhci;
48 struct device *dev;
49 int ret;
50
51 dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev;
52 host = sdhci_alloc_host(dev, sizeof(*sdhci));
53 if (IS_ERR(host)) {
54 ret = PTR_ERR(host);
55 dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
56 goto err;
57 }
58
59 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
60 host->ioaddr = devm_ioremap_resource(&pdev->dev, iomem);
61 if (IS_ERR(host->ioaddr)) {
62 ret = PTR_ERR(host->ioaddr);
63 dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret);
64 goto err_host;
65 }
66
67 host->hw_name = "sdhci";
68 host->ops = &sdhci_pltfm_ops;
69 host->irq = platform_get_irq(pdev, 0);
70 if (host->irq <= 0) {
71 ret = -EINVAL;
72 goto err_host;
73 }
74 host->quirks = SDHCI_QUIRK_BROKEN_ADMA;
75
76 sdhci = sdhci_priv(host);
77
78 /* clk enable */
79 sdhci->clk = devm_clk_get(&pdev->dev, NULL);
80 if (IS_ERR(sdhci->clk)) {
81 ret = PTR_ERR(sdhci->clk);
82 dev_dbg(&pdev->dev, "Error getting clock\n");
83 goto err_host;
84 }
85
86 ret = clk_prepare_enable(sdhci->clk);
87 if (ret) {
88 dev_dbg(&pdev->dev, "Error enabling clock\n");
89 goto err_host;
90 }
91
92 ret = clk_set_rate(sdhci->clk, 50000000);
93 if (ret)
94 dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",
95 clk_get_rate(sdhci->clk));
96
97 /*
98 * It is optional to use GPIOs for sdhci card detection. If we
99 * find a descriptor using slot GPIO, we use it.
100 */
101 ret = mmc_gpiod_request_cd(host->mmc, "cd", 0, false, 0, NULL);
102 if (ret == -EPROBE_DEFER)
103 goto disable_clk;
104
105 ret = sdhci_add_host(host);
106 if (ret)
107 goto disable_clk;
108
109 platform_set_drvdata(pdev, host);
110
111 return 0;
112
113disable_clk:
114 clk_disable_unprepare(sdhci->clk);
115err_host:
116 sdhci_free_host(host);
117err:
118 dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
119 return ret;
120}
121
122static int sdhci_remove(struct platform_device *pdev)
123{
124 struct sdhci_host *host = platform_get_drvdata(pdev);
125 struct spear_sdhci *sdhci = sdhci_priv(host);
126 int dead = 0;
127 u32 scratch;
128
129 scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
130 if (scratch == (u32)-1)
131 dead = 1;
132
133 sdhci_remove_host(host, dead);
134 clk_disable_unprepare(sdhci->clk);
135 sdhci_free_host(host);
136
137 return 0;
138}
139
140#ifdef CONFIG_PM_SLEEP
141static int sdhci_suspend(struct device *dev)
142{
143 struct sdhci_host *host = dev_get_drvdata(dev);
144 struct spear_sdhci *sdhci = sdhci_priv(host);
145 int ret;
146
147 if (host->tuning_mode != SDHCI_TUNING_MODE_3)
148 mmc_retune_needed(host->mmc);
149
150 ret = sdhci_suspend_host(host);
151 if (!ret)
152 clk_disable(sdhci->clk);
153
154 return ret;
155}
156
157static int sdhci_resume(struct device *dev)
158{
159 struct sdhci_host *host = dev_get_drvdata(dev);
160 struct spear_sdhci *sdhci = sdhci_priv(host);
161 int ret;
162
163 ret = clk_enable(sdhci->clk);
164 if (ret) {
165 dev_dbg(dev, "Resume: Error enabling clock\n");
166 return ret;
167 }
168
169 return sdhci_resume_host(host);
170}
171#endif
172
173static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume);
174
175#ifdef CONFIG_OF
176static const struct of_device_id sdhci_spear_id_table[] = {
177 { .compatible = "st,spear300-sdhci" },
178 {}
179};
180MODULE_DEVICE_TABLE(of, sdhci_spear_id_table);
181#endif
182
183static struct platform_driver sdhci_driver = {
184 .driver = {
185 .name = "sdhci",
186 .pm = &sdhci_pm_ops,
187 .of_match_table = of_match_ptr(sdhci_spear_id_table),
188 },
189 .probe = sdhci_probe,
190 .remove = sdhci_remove,
191};
192
193module_platform_driver(sdhci_driver);
194
195MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
196MODULE_AUTHOR("Viresh Kumar <vireshk@kernel.org>");
197MODULE_LICENSE("GPL v2");