summaryrefslogtreecommitdiff
path: root/drivers/mmc/host/sdhci-spear.c
blob: 2dba9f8d1760313e3c47eeca756d6a59247ed924 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
/*
 * drivers/mmc/host/sdhci-spear.c
 *
 * Support of SDHCI platform devices for spear soc family
 *
 * Copyright (C) 2010 ST Microelectronics
 * Viresh Kumar <viresh.linux@gmail.com>
 *
 * Inspired by sdhci-pltfm.c
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/highmem.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/mmc/host.h>
#include <linux/mmc/sdhci-spear.h>
#include <linux/io.h>
#include "sdhci.h"

struct spear_sdhci {
	struct clk *clk;
	struct sdhci_plat_data *data;
};

/* sdhci ops */
static const struct sdhci_ops sdhci_pltfm_ops = {
	/* Nothing to do for now. */
};

/* gpio card detection interrupt handler */
static irqreturn_t sdhci_gpio_irq(int irq, void *dev_id)
{
	struct platform_device *pdev = dev_id;
	struct sdhci_host *host = platform_get_drvdata(pdev);
	struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
	unsigned long gpio_irq_type;
	int val;

	val = gpio_get_value(sdhci->data->card_int_gpio);

	/* val == 1 -> card removed, val == 0 -> card inserted */
	/* if card removed - set irq for low level, else vice versa */
	gpio_irq_type = val ? IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH;
	irq_set_irq_type(irq, gpio_irq_type);

	if (sdhci->data->card_power_gpio >= 0) {
		if (!sdhci->data->power_always_enb) {
			/* if card inserted, give power, otherwise remove it */
			val = sdhci->data->power_active_high ? !val : val ;
			gpio_set_value(sdhci->data->card_power_gpio, val);
		}
	}

	/* inform sdhci driver about card insertion/removal */
	tasklet_schedule(&host->card_tasklet);

	return IRQ_HANDLED;
}

#ifdef CONFIG_OF
static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct sdhci_plat_data *pdata = NULL;
	int cd_gpio;

	cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
	if (!gpio_is_valid(cd_gpio))
		cd_gpio = -1;

	/* If pdata is required */
	if (cd_gpio != -1) {
		pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
		if (!pdata) {
			dev_err(&pdev->dev, "DT: kzalloc failed\n");
			return ERR_PTR(-ENOMEM);
		}
	}

	pdata->card_int_gpio = cd_gpio;

	return pdata;
}
#else
static struct sdhci_plat_data *sdhci_probe_config_dt(struct platform_device *pdev)
{
	return ERR_PTR(-ENOSYS);
}
#endif

static int sdhci_probe(struct platform_device *pdev)
{
	struct device_node *np = pdev->dev.of_node;
	struct sdhci_host *host;
	struct resource *iomem;
	struct spear_sdhci *sdhci;
	int ret;

	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!iomem) {
		ret = -ENOMEM;
		dev_dbg(&pdev->dev, "memory resource not defined\n");
		goto err;
	}

	if (!devm_request_mem_region(&pdev->dev, iomem->start,
				resource_size(iomem), "spear-sdhci")) {
		ret = -EBUSY;
		dev_dbg(&pdev->dev, "cannot request region\n");
		goto err;
	}

	sdhci = devm_kzalloc(&pdev->dev, sizeof(*sdhci), GFP_KERNEL);
	if (!sdhci) {
		ret = -ENOMEM;
		dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
		goto err;
	}

	/* clk enable */
	sdhci->clk = clk_get(&pdev->dev, NULL);
	if (IS_ERR(sdhci->clk)) {
		ret = PTR_ERR(sdhci->clk);
		dev_dbg(&pdev->dev, "Error getting clock\n");
		goto err;
	}

	ret = clk_prepare_enable(sdhci->clk);
	if (ret) {
		dev_dbg(&pdev->dev, "Error enabling clock\n");
		goto put_clk;
	}

	ret = clk_set_rate(sdhci->clk, 50000000);
	if (ret)
		dev_dbg(&pdev->dev, "Error setting desired clk, clk=%lu\n",
				clk_get_rate(sdhci->clk));

	if (np) {
		sdhci->data = sdhci_probe_config_dt(pdev);
		if (IS_ERR(sdhci->data)) {
			dev_err(&pdev->dev, "DT: Failed to get pdata\n");
			return -ENODEV;
		}
	} else {
		sdhci->data = dev_get_platdata(&pdev->dev);
	}

	pdev->dev.platform_data = sdhci;

	if (pdev->dev.parent)
		host = sdhci_alloc_host(pdev->dev.parent, 0);
	else
		host = sdhci_alloc_host(&pdev->dev, 0);

	if (IS_ERR(host)) {
		ret = PTR_ERR(host);
		dev_dbg(&pdev->dev, "error allocating host\n");
		goto disable_clk;
	}

	host->hw_name = "sdhci";
	host->ops = &sdhci_pltfm_ops;
	host->irq = platform_get_irq(pdev, 0);
	host->quirks = SDHCI_QUIRK_BROKEN_ADMA;

	host->ioaddr = devm_ioremap(&pdev->dev, iomem->start,
			resource_size(iomem));
	if (!host->ioaddr) {
		ret = -ENOMEM;
		dev_dbg(&pdev->dev, "failed to remap registers\n");
		goto free_host;
	}

	ret = sdhci_add_host(host);
	if (ret) {
		dev_dbg(&pdev->dev, "error adding host\n");
		goto free_host;
	}

	platform_set_drvdata(pdev, host);

	/*
	 * It is optional to use GPIOs for sdhci Power control & sdhci card
	 * interrupt detection. If sdhci->data is NULL, then use original sdhci
	 * lines otherwise GPIO lines.
	 * If GPIO is selected for power control, then power should be disabled
	 * after card removal and should be enabled when card insertion
	 * interrupt occurs
	 */
	if (!sdhci->data)
		return 0;

	if (sdhci->data->card_power_gpio >= 0) {
		int val = 0;

		ret = devm_gpio_request(&pdev->dev,
				sdhci->data->card_power_gpio, "sdhci");
		if (ret < 0) {
			dev_dbg(&pdev->dev, "gpio request fail: %d\n",
					sdhci->data->card_power_gpio);
			goto set_drvdata;
		}

		if (sdhci->data->power_always_enb)
			val = sdhci->data->power_active_high;
		else
			val = !sdhci->data->power_active_high;

		ret = gpio_direction_output(sdhci->data->card_power_gpio, val);
		if (ret) {
			dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
					sdhci->data->card_power_gpio);
			goto set_drvdata;
		}
	}

	if (sdhci->data->card_int_gpio >= 0) {
		ret = devm_gpio_request(&pdev->dev, sdhci->data->card_int_gpio,
				"sdhci");
		if (ret < 0) {
			dev_dbg(&pdev->dev, "gpio request fail: %d\n",
					sdhci->data->card_int_gpio);
			goto set_drvdata;
		}

		ret = gpio_direction_input(sdhci->data->card_int_gpio);
		if (ret) {
			dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
					sdhci->data->card_int_gpio);
			goto set_drvdata;
		}
		ret = devm_request_irq(&pdev->dev,
				gpio_to_irq(sdhci->data->card_int_gpio),
				sdhci_gpio_irq, IRQF_TRIGGER_LOW,
				mmc_hostname(host->mmc), pdev);
		if (ret) {
			dev_dbg(&pdev->dev, "gpio request irq fail: %d\n",
					sdhci->data->card_int_gpio);
			goto set_drvdata;
		}

	}

	return 0;

set_drvdata:
	sdhci_remove_host(host, 1);
free_host:
	sdhci_free_host(host);
disable_clk:
	clk_disable_unprepare(sdhci->clk);
put_clk:
	clk_put(sdhci->clk);
err:
	dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
	return ret;
}

static int sdhci_remove(struct platform_device *pdev)
{
	struct sdhci_host *host = platform_get_drvdata(pdev);
	struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
	int dead = 0;
	u32 scratch;

	scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
	if (scratch == (u32)-1)
		dead = 1;

	sdhci_remove_host(host, dead);
	sdhci_free_host(host);
	clk_disable_unprepare(sdhci->clk);
	clk_put(sdhci->clk);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int sdhci_suspend(struct device *dev)
{
	struct sdhci_host *host = dev_get_drvdata(dev);
	struct spear_sdhci *sdhci = dev_get_platdata(dev);
	int ret;

	ret = sdhci_suspend_host(host);
	if (!ret)
		clk_disable(sdhci->clk);

	return ret;
}

static int sdhci_resume(struct device *dev)
{
	struct sdhci_host *host = dev_get_drvdata(dev);
	struct spear_sdhci *sdhci = dev_get_platdata(dev);
	int ret;

	ret = clk_enable(sdhci->clk);
	if (ret) {
		dev_dbg(dev, "Resume: Error enabling clock\n");
		return ret;
	}

	return sdhci_resume_host(host);
}
#endif

static SIMPLE_DEV_PM_OPS(sdhci_pm_ops, sdhci_suspend, sdhci_resume);

#ifdef CONFIG_OF
static const struct of_device_id sdhci_spear_id_table[] = {
	{ .compatible = "st,spear300-sdhci" },
	{}
};
MODULE_DEVICE_TABLE(of, sdhci_spear_id_table);
#endif

static struct platform_driver sdhci_driver = {
	.driver = {
		.name	= "sdhci",
		.owner	= THIS_MODULE,
		.pm	= &sdhci_pm_ops,
		.of_match_table = of_match_ptr(sdhci_spear_id_table),
	},
	.probe		= sdhci_probe,
	.remove		= sdhci_remove,
};

module_platform_driver(sdhci_driver);

MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
MODULE_AUTHOR("Viresh Kumar <viresh.linux@gmail.com>");
MODULE_LICENSE("GPL v2");