[go: nahoru, domu]

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 <viresh.linux@gmail.com>
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/sdhci-spear.h>
30#include <linux/mmc/slot-gpio.h>
31#include <linux/io.h>
32#include "sdhci.h"
33
34struct spear_sdhci {
35	struct clk *clk;
36	struct sdhci_plat_data *data;
37};
38
39/* sdhci ops */
40static const struct sdhci_ops sdhci_pltfm_ops = {
41	.set_clock = sdhci_set_clock,
42	.set_bus_width = sdhci_set_bus_width,
43	.reset = sdhci_reset,
44	.set_uhs_signaling = sdhci_set_uhs_signaling,
45};
46
47#ifdef CONFIG_OF
48static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev)
49{
50	struct device_node *np = pdev->dev.of_node;
51	struct sdhci_plat_data *pdata = NULL;
52	int cd_gpio;
53
54	cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
55	if (!gpio_is_valid(cd_gpio))
56		cd_gpio = -1;
57
58	/* If pdata is required */
59	if (cd_gpio != -1) {
60		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
61		if (!pdata)
62			dev_err(&pdev->dev, "DT: kzalloc failed\n");
63		else
64			pdata->card_int_gpio = cd_gpio;
65	}
66
67	return pdata;
68}
69#else
70static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev)
71{
72	return ERR_PTR(-ENOSYS);
73}
74#endif
75
76static int sdhci_probe(struct platform_device *pdev)
77{
78	struct device_node *np = pdev->dev.of_node;
79	struct sdhci_host *host;
80	struct resource *iomem;
81	struct spear_sdhci *sdhci;
82	struct device *dev;
83	int ret;
84
85	dev = pdev->dev.parent ? pdev->dev.parent : &pdev->dev;
86	host = sdhci_alloc_host(dev, sizeof(*sdhci));
87	if (IS_ERR(host)) {
88		ret = PTR_ERR(host);
89		dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
90		goto err;
91	}
92
93	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
94	host->ioaddr = devm_ioremap_resource(&pdev->dev, iomem);
95	if (IS_ERR(host->ioaddr)) {
96		ret = PTR_ERR(host->ioaddr);
97		dev_dbg(&pdev->dev, "unable to map iomem: %d\n", ret);
98		goto err_host;
99	}
100
101	host->hw_name = "sdhci";
102	host->ops = &sdhci_pltfm_ops;
103	host->irq = platform_get_irq(pdev, 0);
104	host->quirks = SDHCI_QUIRK_BROKEN_ADMA;
105
106	sdhci = sdhci_priv(host);
107
108	/* clk enable */
109	sdhci->clk = devm_clk_get(&pdev->dev, NULL);
110	if (IS_ERR(sdhci->clk)) {
111		ret = PTR_ERR(sdhci->clk);
112		dev_dbg(&pdev->dev, "Error getting clock\n");
113		goto err_host;
114	}
115
116	ret = clk_prepare_enable(sdhci->clk);
117	if (ret) {
118		dev_dbg(&pdev->dev, "Error enabling clock\n");
119		goto err_host;
120	}
121
122	ret = clk_set_rate(sdhci->clk, 50000000);
123	if (ret)
124		dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",
125				clk_get_rate(sdhci->clk));
126
127	if (np) {
128		sdhci->data = sdhci_probe_config_dt(pdev);
129		if (IS_ERR(sdhci->data)) {
130			dev_err(&pdev->dev, "DT: Failed to get pdata\n");
131			goto disable_clk;
132		}
133	} else {
134		sdhci->data = dev_get_platdata(&pdev->dev);
135	}
136
137	/*
138	 * It is optional to use GPIOs for sdhci card detection. If
139	 * sdhci->data is NULL, then use original sdhci lines otherwise
140	 * GPIO lines. We use the built-in GPIO support for this.
141	 */
142	if (sdhci->data && sdhci->data->card_int_gpio >= 0) {
143		ret = mmc_gpio_request_cd(host->mmc,
144					  sdhci->data->card_int_gpio, 0);
145		if (ret < 0) {
146			dev_dbg(&pdev->dev,
147				"failed to request card-detect gpio%d\n",
148				sdhci->data->card_int_gpio);
149			goto disable_clk;
150		}
151	}
152
153	ret = sdhci_add_host(host);
154	if (ret) {
155		dev_dbg(&pdev->dev, "error adding host\n");
156		goto disable_clk;
157	}
158
159	platform_set_drvdata(pdev, host);
160
161	return 0;
162
163disable_clk:
164	clk_disable_unprepare(sdhci->clk);
165err_host:
166	sdhci_free_host(host);
167err:
168	dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
169	return ret;
170}
171
172static int sdhci_remove(struct platform_device *pdev)
173{
174	struct sdhci_host *host = platform_get_drvdata(pdev);
175	struct spear_sdhci *sdhci = sdhci_priv(host);
176	int dead = 0;
177	u32 scratch;
178
179	scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
180	if (scratch == (u32)-1)
181		dead = 1;
182
183	sdhci_remove_host(host, dead);
184	clk_disable_unprepare(sdhci->clk);
185	sdhci_free_host(host);
186
187	return 0;
188}
189
190#ifdef CONFIG_PM_SLEEP
191static int sdhci_suspend(struct device *dev)
192{
193	struct sdhci_host *host = dev_get_drvdata(dev);
194	struct spear_sdhci *sdhci = sdhci_priv(host);
195	int ret;
196
197	ret = sdhci_suspend_host(host);
198	if (!ret)
199		clk_disable(sdhci->clk);
200
201	return ret;
202}
203
204static int sdhci_resume(struct device *dev)
205{
206	struct sdhci_host *host = dev_get_drvdata(dev);
207	struct spear_sdhci *sdhci = sdhci_priv(host);
208	int ret;
209
210	ret = clk_enable(sdhci->clk);
211	if (ret) {
212		dev_dbg(dev, "Resume: Error enabling clock\n");
213		return ret;
214	}
215
216	return sdhci_resume_host(host);
217}
218#endif
219
220static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume);
221
222#ifdef CONFIG_OF
223static const struct of_device_id sdhci_spear_id_table[] = {
224	{ .compatible = "st,spear300-sdhci" },
225	{}
226};
227MODULE_DEVICE_TABLE(of, sdhci_spear_id_table);
228#endif
229
230static struct platform_driver sdhci_driver = {
231	.driver = {
232		.name	= "sdhci",
233		.pm	= &sdhci_pm_ops,
234		.of_match_table = of_match_ptr(sdhci_spear_id_table),
235	},
236	.probe		= sdhci_probe,
237	.remove		= sdhci_remove,
238};
239
240module_platform_driver(sdhci_driver);
241
242MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
243MODULE_AUTHOR("Viresh Kumar <viresh.linux@gmail.com>");
244MODULE_LICENSE("GPL v2");
245