1 /*
2 * Copyright (C) 2010 Google, Inc.
3 *
4 * This software is licensed under the terms of the GNU General Public
5 * License version 2, as published by the Free Software Foundation, and
6 * may be copied, distributed, and modified under those terms.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 *
13 */
14
15 #include <linux/err.h>
16 #include <linux/module.h>
17 #include <linux/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/clk.h>
20 #include <linux/io.h>
21 #include <linux/of.h>
22 #include <linux/of_gpio.h>
23 #include <linux/gpio.h>
24 #include <linux/mmc/card.h>
25 #include <linux/mmc/host.h>
26 #include <linux/module.h>
27
28 #include <asm/gpio.h>
29
30 #include <mach/gpio-tegra.h>
31 #include <mach/sdhci.h>
32
33 #include "sdhci-pltfm.h"
34
tegra_sdhci_readl(struct sdhci_host * host,int reg)35 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
36 {
37 u32 val;
38
39 if (unlikely(reg == SDHCI_PRESENT_STATE)) {
40 /* Use wp_gpio here instead? */
41 val = readl(host->ioaddr + reg);
42 return val | SDHCI_WRITE_PROTECT;
43 }
44
45 return readl(host->ioaddr + reg);
46 }
47
tegra_sdhci_readw(struct sdhci_host * host,int reg)48 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
49 {
50 if (unlikely(reg == SDHCI_HOST_VERSION)) {
51 /* Erratum: Version register is invalid in HW. */
52 return SDHCI_SPEC_200;
53 }
54
55 return readw(host->ioaddr + reg);
56 }
57
tegra_sdhci_writel(struct sdhci_host * host,u32 val,int reg)58 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
59 {
60 /* Seems like we're getting spurious timeout and crc errors, so
61 * disable signalling of them. In case of real errors software
62 * timers should take care of eventually detecting them.
63 */
64 if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
65 val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
66
67 writel(val, host->ioaddr + reg);
68
69 if (unlikely(reg == SDHCI_INT_ENABLE)) {
70 /* Erratum: Must enable block gap interrupt detection */
71 u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
72 if (val & SDHCI_INT_CARD_INT)
73 gap_ctrl |= 0x8;
74 else
75 gap_ctrl &= ~0x8;
76 writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
77 }
78 }
79
tegra_sdhci_get_ro(struct sdhci_host * sdhci)80 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *sdhci)
81 {
82 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(sdhci);
83 struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
84
85 if (!gpio_is_valid(plat->wp_gpio))
86 return -1;
87
88 return gpio_get_value(plat->wp_gpio);
89 }
90
carddetect_irq(int irq,void * data)91 static irqreturn_t carddetect_irq(int irq, void *data)
92 {
93 struct sdhci_host *sdhost = (struct sdhci_host *)data;
94
95 tasklet_schedule(&sdhost->card_tasklet);
96 return IRQ_HANDLED;
97 };
98
tegra_sdhci_8bit(struct sdhci_host * host,int bus_width)99 static int tegra_sdhci_8bit(struct sdhci_host *host, int bus_width)
100 {
101 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
102 struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
103 u32 ctrl;
104
105 ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
106 if (plat->is_8bit && bus_width == MMC_BUS_WIDTH_8) {
107 ctrl &= ~SDHCI_CTRL_4BITBUS;
108 ctrl |= SDHCI_CTRL_8BITBUS;
109 } else {
110 ctrl &= ~SDHCI_CTRL_8BITBUS;
111 if (bus_width == MMC_BUS_WIDTH_4)
112 ctrl |= SDHCI_CTRL_4BITBUS;
113 else
114 ctrl &= ~SDHCI_CTRL_4BITBUS;
115 }
116 sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
117 return 0;
118 }
119
120 static struct sdhci_ops tegra_sdhci_ops = {
121 .get_ro = tegra_sdhci_get_ro,
122 .read_l = tegra_sdhci_readl,
123 .read_w = tegra_sdhci_readw,
124 .write_l = tegra_sdhci_writel,
125 .platform_8bit_width = tegra_sdhci_8bit,
126 };
127
128 static struct sdhci_pltfm_data sdhci_tegra_pdata = {
129 .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
130 SDHCI_QUIRK_SINGLE_POWER_WRITE |
131 SDHCI_QUIRK_NO_HISPD_BIT |
132 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
133 .ops = &tegra_sdhci_ops,
134 };
135
136 static const struct of_device_id sdhci_tegra_dt_match[] __devinitdata = {
137 { .compatible = "nvidia,tegra20-sdhci", },
138 {}
139 };
140 MODULE_DEVICE_TABLE(of, sdhci_dt_ids);
141
sdhci_tegra_dt_parse_pdata(struct platform_device * pdev)142 static struct tegra_sdhci_platform_data * __devinit sdhci_tegra_dt_parse_pdata(
143 struct platform_device *pdev)
144 {
145 struct tegra_sdhci_platform_data *plat;
146 struct device_node *np = pdev->dev.of_node;
147
148 if (!np)
149 return NULL;
150
151 plat = devm_kzalloc(&pdev->dev, sizeof(*plat), GFP_KERNEL);
152 if (!plat) {
153 dev_err(&pdev->dev, "Can't allocate platform data\n");
154 return NULL;
155 }
156
157 plat->cd_gpio = of_get_named_gpio(np, "cd-gpios", 0);
158 plat->wp_gpio = of_get_named_gpio(np, "wp-gpios", 0);
159 plat->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
160 if (of_find_property(np, "support-8bit", NULL))
161 plat->is_8bit = 1;
162
163 return plat;
164 }
165
sdhci_tegra_probe(struct platform_device * pdev)166 static int __devinit sdhci_tegra_probe(struct platform_device *pdev)
167 {
168 struct sdhci_pltfm_host *pltfm_host;
169 struct tegra_sdhci_platform_data *plat;
170 struct sdhci_host *host;
171 struct clk *clk;
172 int rc;
173
174 host = sdhci_pltfm_init(pdev, &sdhci_tegra_pdata);
175 if (IS_ERR(host))
176 return PTR_ERR(host);
177
178 pltfm_host = sdhci_priv(host);
179
180 plat = pdev->dev.platform_data;
181
182 if (plat == NULL)
183 plat = sdhci_tegra_dt_parse_pdata(pdev);
184
185 if (plat == NULL) {
186 dev_err(mmc_dev(host->mmc), "missing platform data\n");
187 rc = -ENXIO;
188 goto err_no_plat;
189 }
190
191 pltfm_host->priv = plat;
192
193 if (gpio_is_valid(plat->power_gpio)) {
194 rc = gpio_request(plat->power_gpio, "sdhci_power");
195 if (rc) {
196 dev_err(mmc_dev(host->mmc),
197 "failed to allocate power gpio\n");
198 goto err_power_req;
199 }
200 tegra_gpio_enable(plat->power_gpio);
201 gpio_direction_output(plat->power_gpio, 1);
202 }
203
204 if (gpio_is_valid(plat->cd_gpio)) {
205 rc = gpio_request(plat->cd_gpio, "sdhci_cd");
206 if (rc) {
207 dev_err(mmc_dev(host->mmc),
208 "failed to allocate cd gpio\n");
209 goto err_cd_req;
210 }
211 tegra_gpio_enable(plat->cd_gpio);
212 gpio_direction_input(plat->cd_gpio);
213
214 rc = request_irq(gpio_to_irq(plat->cd_gpio), carddetect_irq,
215 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
216 mmc_hostname(host->mmc), host);
217
218 if (rc) {
219 dev_err(mmc_dev(host->mmc), "request irq error\n");
220 goto err_cd_irq_req;
221 }
222
223 }
224
225 if (gpio_is_valid(plat->wp_gpio)) {
226 rc = gpio_request(plat->wp_gpio, "sdhci_wp");
227 if (rc) {
228 dev_err(mmc_dev(host->mmc),
229 "failed to allocate wp gpio\n");
230 goto err_wp_req;
231 }
232 tegra_gpio_enable(plat->wp_gpio);
233 gpio_direction_input(plat->wp_gpio);
234 }
235
236 clk = clk_get(mmc_dev(host->mmc), NULL);
237 if (IS_ERR(clk)) {
238 dev_err(mmc_dev(host->mmc), "clk err\n");
239 rc = PTR_ERR(clk);
240 goto err_clk_get;
241 }
242 clk_enable(clk);
243 pltfm_host->clk = clk;
244
245 host->mmc->pm_caps = plat->pm_flags;
246
247 if (plat->is_8bit)
248 host->mmc->caps |= MMC_CAP_8_BIT_DATA;
249
250 rc = sdhci_add_host(host);
251 if (rc)
252 goto err_add_host;
253
254 return 0;
255
256 err_add_host:
257 clk_disable(pltfm_host->clk);
258 clk_put(pltfm_host->clk);
259 err_clk_get:
260 if (gpio_is_valid(plat->wp_gpio)) {
261 tegra_gpio_disable(plat->wp_gpio);
262 gpio_free(plat->wp_gpio);
263 }
264 err_wp_req:
265 if (gpio_is_valid(plat->cd_gpio))
266 free_irq(gpio_to_irq(plat->cd_gpio), host);
267 err_cd_irq_req:
268 if (gpio_is_valid(plat->cd_gpio)) {
269 tegra_gpio_disable(plat->cd_gpio);
270 gpio_free(plat->cd_gpio);
271 }
272 err_cd_req:
273 if (gpio_is_valid(plat->power_gpio)) {
274 tegra_gpio_disable(plat->power_gpio);
275 gpio_free(plat->power_gpio);
276 }
277 err_power_req:
278 err_no_plat:
279 sdhci_pltfm_free(pdev);
280 return rc;
281 }
282
sdhci_tegra_remove(struct platform_device * pdev)283 static int __devexit sdhci_tegra_remove(struct platform_device *pdev)
284 {
285 struct sdhci_host *host = platform_get_drvdata(pdev);
286 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
287 struct tegra_sdhci_platform_data *plat = pltfm_host->priv;
288 int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
289
290 sdhci_remove_host(host, dead);
291
292 if (gpio_is_valid(plat->wp_gpio)) {
293 tegra_gpio_disable(plat->wp_gpio);
294 gpio_free(plat->wp_gpio);
295 }
296
297 if (gpio_is_valid(plat->cd_gpio)) {
298 free_irq(gpio_to_irq(plat->cd_gpio), host);
299 tegra_gpio_disable(plat->cd_gpio);
300 gpio_free(plat->cd_gpio);
301 }
302
303 if (gpio_is_valid(plat->power_gpio)) {
304 tegra_gpio_disable(plat->power_gpio);
305 gpio_free(plat->power_gpio);
306 }
307
308 clk_disable(pltfm_host->clk);
309 clk_put(pltfm_host->clk);
310
311 sdhci_pltfm_free(pdev);
312
313 return 0;
314 }
315
316 static struct platform_driver sdhci_tegra_driver = {
317 .driver = {
318 .name = "sdhci-tegra",
319 .owner = THIS_MODULE,
320 .of_match_table = sdhci_tegra_dt_match,
321 .pm = SDHCI_PLTFM_PMOPS,
322 },
323 .probe = sdhci_tegra_probe,
324 .remove = __devexit_p(sdhci_tegra_remove),
325 };
326
327 module_platform_driver(sdhci_tegra_driver);
328
329 MODULE_DESCRIPTION("SDHCI driver for Tegra");
330 MODULE_AUTHOR(" Google, Inc.");
331 MODULE_LICENSE("GPL v2");
332