xref: /linux/drivers/mmc/host/sdhci-spear.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
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.kumar@st.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/platform_device.h>
24 #include <linux/slab.h>
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/sdhci-spear.h>
27 #include <linux/io.h>
28 #include "sdhci.h"
29 
30 struct spear_sdhci {
31 	struct clk *clk;
32 	struct sdhci_plat_data *data;
33 };
34 
35 /* sdhci ops */
36 static struct sdhci_ops sdhci_pltfm_ops = {
37 	/* Nothing to do for now. */
38 };
39 
40 /* gpio card detection interrupt handler */
41 static irqreturn_t sdhci_gpio_irq(int irq, void *dev_id)
42 {
43 	struct platform_device *pdev = dev_id;
44 	struct sdhci_host *host = platform_get_drvdata(pdev);
45 	struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
46 	unsigned long gpio_irq_type;
47 	int val;
48 
49 	val = gpio_get_value(sdhci->data->card_int_gpio);
50 
51 	/* val == 1 -> card removed, val == 0 -> card inserted */
52 	/* if card removed - set irq for low level, else vice versa */
53 	gpio_irq_type = val ? IRQF_TRIGGER_LOW : IRQF_TRIGGER_HIGH;
54 	irq_set_irq_type(irq, gpio_irq_type);
55 
56 	if (sdhci->data->card_power_gpio >= 0) {
57 		if (!sdhci->data->power_always_enb) {
58 			/* if card inserted, give power, otherwise remove it */
59 			val = sdhci->data->power_active_high ? !val : val ;
60 			gpio_set_value(sdhci->data->card_power_gpio, val);
61 		}
62 	}
63 
64 	/* inform sdhci driver about card insertion/removal */
65 	tasklet_schedule(&host->card_tasklet);
66 
67 	return IRQ_HANDLED;
68 }
69 
70 static int __devinit sdhci_probe(struct platform_device *pdev)
71 {
72 	struct sdhci_host *host;
73 	struct resource *iomem;
74 	struct spear_sdhci *sdhci;
75 	int ret;
76 
77 	BUG_ON(pdev == NULL);
78 
79 	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
80 	if (!iomem) {
81 		ret = -ENOMEM;
82 		dev_dbg(&pdev->dev, "memory resource not defined\n");
83 		goto err;
84 	}
85 
86 	if (!request_mem_region(iomem->start, resource_size(iomem),
87 				"spear-sdhci")) {
88 		ret = -EBUSY;
89 		dev_dbg(&pdev->dev, "cannot request region\n");
90 		goto err;
91 	}
92 
93 	sdhci = kzalloc(sizeof(*sdhci), GFP_KERNEL);
94 	if (!sdhci) {
95 		ret = -ENOMEM;
96 		dev_dbg(&pdev->dev, "cannot allocate memory for sdhci\n");
97 		goto err_kzalloc;
98 	}
99 
100 	/* clk enable */
101 	sdhci->clk = clk_get(&pdev->dev, NULL);
102 	if (IS_ERR(sdhci->clk)) {
103 		ret = PTR_ERR(sdhci->clk);
104 		dev_dbg(&pdev->dev, "Error getting clock\n");
105 		goto err_clk_get;
106 	}
107 
108 	ret = clk_enable(sdhci->clk);
109 	if (ret) {
110 		dev_dbg(&pdev->dev, "Error enabling clock\n");
111 		goto err_clk_enb;
112 	}
113 
114 	/* overwrite platform_data */
115 	sdhci->data = dev_get_platdata(&pdev->dev);
116 	pdev->dev.platform_data = sdhci;
117 
118 	if (pdev->dev.parent)
119 		host = sdhci_alloc_host(pdev->dev.parent, 0);
120 	else
121 		host = sdhci_alloc_host(&pdev->dev, 0);
122 
123 	if (IS_ERR(host)) {
124 		ret = PTR_ERR(host);
125 		dev_dbg(&pdev->dev, "error allocating host\n");
126 		goto err_alloc_host;
127 	}
128 
129 	host->hw_name = "sdhci";
130 	host->ops = &sdhci_pltfm_ops;
131 	host->irq = platform_get_irq(pdev, 0);
132 	host->quirks = SDHCI_QUIRK_BROKEN_ADMA;
133 
134 	host->ioaddr = ioremap(iomem->start, resource_size(iomem));
135 	if (!host->ioaddr) {
136 		ret = -ENOMEM;
137 		dev_dbg(&pdev->dev, "failed to remap registers\n");
138 		goto err_ioremap;
139 	}
140 
141 	ret = sdhci_add_host(host);
142 	if (ret) {
143 		dev_dbg(&pdev->dev, "error adding host\n");
144 		goto err_add_host;
145 	}
146 
147 	platform_set_drvdata(pdev, host);
148 
149 	/*
150 	 * It is optional to use GPIOs for sdhci Power control & sdhci card
151 	 * interrupt detection. If sdhci->data is NULL, then use original sdhci
152 	 * lines otherwise GPIO lines.
153 	 * If GPIO is selected for power control, then power should be disabled
154 	 * after card removal and should be enabled when card insertion
155 	 * interrupt occurs
156 	 */
157 	if (!sdhci->data)
158 		return 0;
159 
160 	if (sdhci->data->card_power_gpio >= 0) {
161 		int val = 0;
162 
163 		ret = gpio_request(sdhci->data->card_power_gpio, "sdhci");
164 		if (ret < 0) {
165 			dev_dbg(&pdev->dev, "gpio request fail: %d\n",
166 					sdhci->data->card_power_gpio);
167 			goto err_pgpio_request;
168 		}
169 
170 		if (sdhci->data->power_always_enb)
171 			val = sdhci->data->power_active_high;
172 		else
173 			val = !sdhci->data->power_active_high;
174 
175 		ret = gpio_direction_output(sdhci->data->card_power_gpio, val);
176 		if (ret) {
177 			dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
178 					sdhci->data->card_power_gpio);
179 			goto err_pgpio_direction;
180 		}
181 	}
182 
183 	if (sdhci->data->card_int_gpio >= 0) {
184 		ret = gpio_request(sdhci->data->card_int_gpio, "sdhci");
185 		if (ret < 0) {
186 			dev_dbg(&pdev->dev, "gpio request fail: %d\n",
187 					sdhci->data->card_int_gpio);
188 			goto err_igpio_request;
189 		}
190 
191 		ret = gpio_direction_input(sdhci->data->card_int_gpio);
192 		if (ret) {
193 			dev_dbg(&pdev->dev, "gpio set direction fail: %d\n",
194 					sdhci->data->card_int_gpio);
195 			goto err_igpio_direction;
196 		}
197 		ret = request_irq(gpio_to_irq(sdhci->data->card_int_gpio),
198 				sdhci_gpio_irq, IRQF_TRIGGER_LOW,
199 				mmc_hostname(host->mmc), pdev);
200 		if (ret) {
201 			dev_dbg(&pdev->dev, "gpio request irq fail: %d\n",
202 					sdhci->data->card_int_gpio);
203 			goto err_igpio_request_irq;
204 		}
205 
206 	}
207 
208 	return 0;
209 
210 err_igpio_request_irq:
211 err_igpio_direction:
212 	if (sdhci->data->card_int_gpio >= 0)
213 		gpio_free(sdhci->data->card_int_gpio);
214 err_igpio_request:
215 err_pgpio_direction:
216 	if (sdhci->data->card_power_gpio >= 0)
217 		gpio_free(sdhci->data->card_power_gpio);
218 err_pgpio_request:
219 	platform_set_drvdata(pdev, NULL);
220 	sdhci_remove_host(host, 1);
221 err_add_host:
222 	iounmap(host->ioaddr);
223 err_ioremap:
224 	sdhci_free_host(host);
225 err_alloc_host:
226 	clk_disable(sdhci->clk);
227 err_clk_enb:
228 	clk_put(sdhci->clk);
229 err_clk_get:
230 	kfree(sdhci);
231 err_kzalloc:
232 	release_mem_region(iomem->start, resource_size(iomem));
233 err:
234 	dev_err(&pdev->dev, "spear-sdhci probe failed: %d\n", ret);
235 	return ret;
236 }
237 
238 static int __devexit sdhci_remove(struct platform_device *pdev)
239 {
240 	struct sdhci_host *host = platform_get_drvdata(pdev);
241 	struct resource *iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
242 	struct spear_sdhci *sdhci = dev_get_platdata(&pdev->dev);
243 	int dead;
244 	u32 scratch;
245 
246 	if (sdhci->data) {
247 		if (sdhci->data->card_int_gpio >= 0) {
248 			free_irq(gpio_to_irq(sdhci->data->card_int_gpio), pdev);
249 			gpio_free(sdhci->data->card_int_gpio);
250 		}
251 
252 		if (sdhci->data->card_power_gpio >= 0)
253 			gpio_free(sdhci->data->card_power_gpio);
254 	}
255 
256 	platform_set_drvdata(pdev, NULL);
257 	dead = 0;
258 	scratch = readl(host->ioaddr + SDHCI_INT_STATUS);
259 	if (scratch == (u32)-1)
260 		dead = 1;
261 
262 	sdhci_remove_host(host, dead);
263 	iounmap(host->ioaddr);
264 	sdhci_free_host(host);
265 	clk_disable(sdhci->clk);
266 	clk_put(sdhci->clk);
267 	kfree(sdhci);
268 	if (iomem)
269 		release_mem_region(iomem->start, resource_size(iomem));
270 
271 	return 0;
272 }
273 
274 static struct platform_driver sdhci_driver = {
275 	.driver = {
276 		.name	= "sdhci",
277 		.owner	= THIS_MODULE,
278 	},
279 	.probe		= sdhci_probe,
280 	.remove		= __devexit_p(sdhci_remove),
281 };
282 
283 static int __init sdhci_init(void)
284 {
285 	return platform_driver_register(&sdhci_driver);
286 }
287 module_init(sdhci_init);
288 
289 static void __exit sdhci_exit(void)
290 {
291 	platform_driver_unregister(&sdhci_driver);
292 }
293 module_exit(sdhci_exit);
294 
295 MODULE_DESCRIPTION("SPEAr Secure Digital Host Controller Interface driver");
296 MODULE_AUTHOR("Viresh Kumar <viresh.kumar@st.com>");
297 MODULE_LICENSE("GPL v2");
298