1 /*
2  * Freescale eSDHC i.MX controller driver for the platform bus.
3  *
4  * derived from the OF-version.
5  *
6  * Copyright (c) 2010 Pengutronix e.K.
7  *   Author: Wolfram Sang <w.sang@pengutronix.de>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License.
12  */
13 
14 #include <linux/io.h>
15 #include <linux/delay.h>
16 #include <linux/err.h>
17 #include <linux/clk.h>
18 #include <linux/gpio.h>
19 #include <linux/slab.h>
20 #include <linux/mmc/host.h>
21 #include <linux/mmc/mmc.h>
22 #include <linux/mmc/sdio.h>
23 #include <mach/hardware.h>
24 #include <mach/esdhc.h>
25 #include "sdhci-pltfm.h"
26 #include "sdhci-esdhc.h"
27 
28 /* VENDOR SPEC register */
29 #define SDHCI_VENDOR_SPEC		0xC0
30 #define  SDHCI_VENDOR_SPEC_SDIO_QUIRK	0x00000002
31 
32 #define ESDHC_FLAG_GPIO_FOR_CD		(1 << 0)
33 /*
34  * The CMDTYPE of the CMD register (offset 0xE) should be set to
35  * "11" when the STOP CMD12 is issued on imx53 to abort one
36  * open ended multi-blk IO. Otherwise the TC INT wouldn't
37  * be generated.
38  * In exact block transfer, the controller doesn't complete the
39  * operations automatically as required at the end of the
40  * transfer and remains on hold if the abort command is not sent.
41  * As a result, the TC flag is not asserted and SW  received timeout
42  * exeception. Bit1 of Vendor Spec registor is used to fix it.
43  */
44 #define ESDHC_FLAG_MULTIBLK_NO_INT	(1 << 1)
45 
46 struct pltfm_imx_data {
47 	int flags;
48 	u32 scratchpad;
49 };
50 
51 static inline void esdhc_clrset_le(struct sdhci_host *host, u32 mask, u32 val, int reg)
52 {
53 	void __iomem *base = host->ioaddr + (reg & ~0x3);
54 	u32 shift = (reg & 0x3) * 8;
55 
56 	writel(((readl(base) & ~(mask << shift)) | (val << shift)), base);
57 }
58 
59 static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
60 {
61 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
62 	struct pltfm_imx_data *imx_data = pltfm_host->priv;
63 
64 	/* fake CARD_PRESENT flag on mx25/35 */
65 	u32 val = readl(host->ioaddr + reg);
66 
67 	if (unlikely((reg == SDHCI_PRESENT_STATE)
68 			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD))) {
69 		struct esdhc_platform_data *boarddata =
70 				host->mmc->parent->platform_data;
71 
72 		if (boarddata && gpio_is_valid(boarddata->cd_gpio)
73 				&& gpio_get_value(boarddata->cd_gpio))
74 			/* no card, if a valid gpio says so... */
75 			val &= ~SDHCI_CARD_PRESENT;
76 		else
77 			/* ... in all other cases assume card is present */
78 			val |= SDHCI_CARD_PRESENT;
79 	}
80 
81 	return val;
82 }
83 
84 static void esdhc_writel_le(struct sdhci_host *host, u32 val, int reg)
85 {
86 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
87 	struct pltfm_imx_data *imx_data = pltfm_host->priv;
88 
89 	if (unlikely((reg == SDHCI_INT_ENABLE || reg == SDHCI_SIGNAL_ENABLE)
90 			&& (imx_data->flags & ESDHC_FLAG_GPIO_FOR_CD)))
91 		/*
92 		 * these interrupts won't work with a custom card_detect gpio
93 		 * (only applied to mx25/35)
94 		 */
95 		val &= ~(SDHCI_INT_CARD_REMOVE | SDHCI_INT_CARD_INSERT);
96 
97 	if (unlikely((imx_data->flags & ESDHC_FLAG_MULTIBLK_NO_INT)
98 				&& (reg == SDHCI_INT_STATUS)
99 				&& (val & SDHCI_INT_DATA_END))) {
100 			u32 v;
101 			v = readl(host->ioaddr + SDHCI_VENDOR_SPEC);
102 			v &= ~SDHCI_VENDOR_SPEC_SDIO_QUIRK;
103 			writel(v, host->ioaddr + SDHCI_VENDOR_SPEC);
104 	}
105 
106 	writel(val, host->ioaddr + reg);
107 }
108 
109 static u16 esdhc_readw_le(struct sdhci_host *host, int reg)
110 {
111 	if (unlikely(reg == SDHCI_HOST_VERSION))
112 		reg ^= 2;
113 
114 	return readw(host->ioaddr + reg);
115 }
116 
117 static void esdhc_writew_le(struct sdhci_host *host, u16 val, int reg)
118 {
119 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
120 	struct pltfm_imx_data *imx_data = pltfm_host->priv;
121 
122 	switch (reg) {
123 	case SDHCI_TRANSFER_MODE:
124 		/*
125 		 * Postpone this write, we must do it together with a
126 		 * command write that is down below.
127 		 */
128 		if ((imx_data->flags & ESDHC_FLAG_MULTIBLK_NO_INT)
129 				&& (host->cmd->opcode == SD_IO_RW_EXTENDED)
130 				&& (host->cmd->data->blocks > 1)
131 				&& (host->cmd->data->flags & MMC_DATA_READ)) {
132 			u32 v;
133 			v = readl(host->ioaddr + SDHCI_VENDOR_SPEC);
134 			v |= SDHCI_VENDOR_SPEC_SDIO_QUIRK;
135 			writel(v, host->ioaddr + SDHCI_VENDOR_SPEC);
136 		}
137 		imx_data->scratchpad = val;
138 		return;
139 	case SDHCI_COMMAND:
140 		if ((host->cmd->opcode == MMC_STOP_TRANSMISSION)
141 			&& (imx_data->flags & ESDHC_FLAG_MULTIBLK_NO_INT))
142 			val |= SDHCI_CMD_ABORTCMD;
143 		writel(val << 16 | imx_data->scratchpad,
144 			host->ioaddr + SDHCI_TRANSFER_MODE);
145 		return;
146 	case SDHCI_BLOCK_SIZE:
147 		val &= ~SDHCI_MAKE_BLKSZ(0x7, 0);
148 		break;
149 	}
150 	esdhc_clrset_le(host, 0xffff, val, reg);
151 }
152 
153 static void esdhc_writeb_le(struct sdhci_host *host, u8 val, int reg)
154 {
155 	u32 new_val;
156 
157 	switch (reg) {
158 	case SDHCI_POWER_CONTROL:
159 		/*
160 		 * FSL put some DMA bits here
161 		 * If your board has a regulator, code should be here
162 		 */
163 		return;
164 	case SDHCI_HOST_CONTROL:
165 		/* FSL messed up here, so we can just keep those two */
166 		new_val = val & (SDHCI_CTRL_LED | SDHCI_CTRL_4BITBUS);
167 		/* ensure the endianess */
168 		new_val |= ESDHC_HOST_CONTROL_LE;
169 		/* DMA mode bits are shifted */
170 		new_val |= (val & SDHCI_CTRL_DMA_MASK) << 5;
171 
172 		esdhc_clrset_le(host, 0xffff, new_val, reg);
173 		return;
174 	}
175 	esdhc_clrset_le(host, 0xff, val, reg);
176 }
177 
178 static unsigned int esdhc_pltfm_get_max_clock(struct sdhci_host *host)
179 {
180 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
181 
182 	return clk_get_rate(pltfm_host->clk);
183 }
184 
185 static unsigned int esdhc_pltfm_get_min_clock(struct sdhci_host *host)
186 {
187 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
188 
189 	return clk_get_rate(pltfm_host->clk) / 256 / 16;
190 }
191 
192 static struct sdhci_ops sdhci_esdhc_ops = {
193 	.read_l = esdhc_readl_le,
194 	.read_w = esdhc_readw_le,
195 	.write_l = esdhc_writel_le,
196 	.write_w = esdhc_writew_le,
197 	.write_b = esdhc_writeb_le,
198 	.set_clock = esdhc_set_clock,
199 	.get_max_clock = esdhc_pltfm_get_max_clock,
200 	.get_min_clock = esdhc_pltfm_get_min_clock,
201 };
202 
203 static struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = {
204 	.quirks = ESDHC_DEFAULT_QUIRKS | SDHCI_QUIRK_BROKEN_ADMA
205 			| SDHCI_QUIRK_BROKEN_CARD_DETECTION,
206 	/* ADMA has issues. Might be fixable */
207 	.ops = &sdhci_esdhc_ops,
208 };
209 
210 static unsigned int esdhc_pltfm_get_ro(struct sdhci_host *host)
211 {
212 	struct esdhc_platform_data *boarddata =
213 			host->mmc->parent->platform_data;
214 
215 	if (boarddata && gpio_is_valid(boarddata->wp_gpio))
216 		return gpio_get_value(boarddata->wp_gpio);
217 	else
218 		return -ENOSYS;
219 }
220 
221 static irqreturn_t cd_irq(int irq, void *data)
222 {
223 	struct sdhci_host *sdhost = (struct sdhci_host *)data;
224 
225 	tasklet_schedule(&sdhost->card_tasklet);
226 	return IRQ_HANDLED;
227 };
228 
229 static int __devinit sdhci_esdhc_imx_probe(struct platform_device *pdev)
230 {
231 	struct sdhci_pltfm_host *pltfm_host;
232 	struct sdhci_host *host;
233 	struct esdhc_platform_data *boarddata;
234 	struct clk *clk;
235 	int err;
236 	struct pltfm_imx_data *imx_data;
237 
238 	host = sdhci_pltfm_init(pdev, &sdhci_esdhc_imx_pdata);
239 	if (IS_ERR(host))
240 		return PTR_ERR(host);
241 
242 	pltfm_host = sdhci_priv(host);
243 
244 	imx_data = kzalloc(sizeof(struct pltfm_imx_data), GFP_KERNEL);
245 	if (!imx_data)
246 		return -ENOMEM;
247 	pltfm_host->priv = imx_data;
248 
249 	clk = clk_get(mmc_dev(host->mmc), NULL);
250 	if (IS_ERR(clk)) {
251 		dev_err(mmc_dev(host->mmc), "clk err\n");
252 		err = PTR_ERR(clk);
253 		goto err_clk_get;
254 	}
255 	clk_enable(clk);
256 	pltfm_host->clk = clk;
257 
258 	if (!cpu_is_mx25())
259 		host->quirks |= SDHCI_QUIRK_BROKEN_TIMEOUT_VAL;
260 
261 	if (cpu_is_mx25() || cpu_is_mx35()) {
262 		/* Fix errata ENGcm07207 present on i.MX25 and i.MX35 */
263 		host->quirks |= SDHCI_QUIRK_NO_MULTIBLOCK;
264 		/* write_protect can't be routed to controller, use gpio */
265 		sdhci_esdhc_ops.get_ro = esdhc_pltfm_get_ro;
266 	}
267 
268 	if (!(cpu_is_mx25() || cpu_is_mx35() || cpu_is_mx51()))
269 		imx_data->flags |= ESDHC_FLAG_MULTIBLK_NO_INT;
270 
271 	boarddata = host->mmc->parent->platform_data;
272 	if (boarddata) {
273 		err = gpio_request_one(boarddata->wp_gpio, GPIOF_IN, "ESDHC_WP");
274 		if (err) {
275 			dev_warn(mmc_dev(host->mmc),
276 				"no write-protect pin available!\n");
277 			boarddata->wp_gpio = err;
278 		}
279 
280 		err = gpio_request_one(boarddata->cd_gpio, GPIOF_IN, "ESDHC_CD");
281 		if (err) {
282 			dev_warn(mmc_dev(host->mmc),
283 				"no card-detect pin available!\n");
284 			goto no_card_detect_pin;
285 		}
286 
287 		/* i.MX5x has issues to be researched */
288 		if (!cpu_is_mx25() && !cpu_is_mx35())
289 			goto not_supported;
290 
291 		err = request_irq(gpio_to_irq(boarddata->cd_gpio), cd_irq,
292 				 IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
293 				 mmc_hostname(host->mmc), host);
294 		if (err) {
295 			dev_warn(mmc_dev(host->mmc), "request irq error\n");
296 			goto no_card_detect_irq;
297 		}
298 
299 		imx_data->flags |= ESDHC_FLAG_GPIO_FOR_CD;
300 		/* Now we have a working card_detect again */
301 		host->quirks &= ~SDHCI_QUIRK_BROKEN_CARD_DETECTION;
302 	}
303 
304 	err = sdhci_add_host(host);
305 	if (err)
306 		goto err_add_host;
307 
308 	return 0;
309 
310  no_card_detect_irq:
311 	gpio_free(boarddata->cd_gpio);
312  no_card_detect_pin:
313 	boarddata->cd_gpio = err;
314  not_supported:
315 	kfree(imx_data);
316  err_add_host:
317 	clk_disable(pltfm_host->clk);
318 	clk_put(pltfm_host->clk);
319  err_clk_get:
320 	sdhci_pltfm_free(pdev);
321 	return err;
322 }
323 
324 static int __devexit sdhci_esdhc_imx_remove(struct platform_device *pdev)
325 {
326 	struct sdhci_host *host = platform_get_drvdata(pdev);
327 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
328 	struct esdhc_platform_data *boarddata = host->mmc->parent->platform_data;
329 	struct pltfm_imx_data *imx_data = pltfm_host->priv;
330 	int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
331 
332 	sdhci_remove_host(host, dead);
333 
334 	if (boarddata && gpio_is_valid(boarddata->wp_gpio))
335 		gpio_free(boarddata->wp_gpio);
336 
337 	if (boarddata && gpio_is_valid(boarddata->cd_gpio)) {
338 		gpio_free(boarddata->cd_gpio);
339 
340 		if (!(host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION))
341 			free_irq(gpio_to_irq(boarddata->cd_gpio), host);
342 	}
343 
344 	clk_disable(pltfm_host->clk);
345 	clk_put(pltfm_host->clk);
346 	kfree(imx_data);
347 
348 	sdhci_pltfm_free(pdev);
349 
350 	return 0;
351 }
352 
353 static struct platform_driver sdhci_esdhc_imx_driver = {
354 	.driver		= {
355 		.name	= "sdhci-esdhc-imx",
356 		.owner	= THIS_MODULE,
357 	},
358 	.probe		= sdhci_esdhc_imx_probe,
359 	.remove		= __devexit_p(sdhci_esdhc_imx_remove),
360 #ifdef CONFIG_PM
361 	.suspend	= sdhci_pltfm_suspend,
362 	.resume		= sdhci_pltfm_resume,
363 #endif
364 };
365 
366 static int __init sdhci_esdhc_imx_init(void)
367 {
368 	return platform_driver_register(&sdhci_esdhc_imx_driver);
369 }
370 module_init(sdhci_esdhc_imx_init);
371 
372 static void __exit sdhci_esdhc_imx_exit(void)
373 {
374 	platform_driver_unregister(&sdhci_esdhc_imx_driver);
375 }
376 module_exit(sdhci_esdhc_imx_exit);
377 
378 MODULE_DESCRIPTION("SDHCI driver for Freescale i.MX eSDHC");
379 MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
380 MODULE_LICENSE("GPL v2");
381