xref: /openbmc/linux/drivers/mmc/host/sdhci-dove.c (revision b34e08d5)
1 /*
2  * sdhci-dove.c Support for SDHCI on Marvell's Dove SoC
3  *
4  * Author: Saeed Bishara <saeed@marvell.com>
5  *	   Mike Rapoport <mike@compulab.co.il>
6  * Based on sdhci-cns3xxx.c
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 #include <linux/clk.h>
23 #include <linux/err.h>
24 #include <linux/gpio.h>
25 #include <linux/io.h>
26 #include <linux/mmc/host.h>
27 #include <linux/module.h>
28 #include <linux/of.h>
29 #include <linux/of_gpio.h>
30 
31 #include "sdhci-pltfm.h"
32 
33 struct sdhci_dove_priv {
34 	struct clk *clk;
35 	int gpio_cd;
36 };
37 
38 static irqreturn_t sdhci_dove_carddetect_irq(int irq, void *data)
39 {
40 	struct sdhci_host *host = data;
41 
42 	tasklet_schedule(&host->card_tasklet);
43 	return IRQ_HANDLED;
44 }
45 
46 static u16 sdhci_dove_readw(struct sdhci_host *host, int reg)
47 {
48 	u16 ret;
49 
50 	switch (reg) {
51 	case SDHCI_HOST_VERSION:
52 	case SDHCI_SLOT_INT_STATUS:
53 		/* those registers don't exist */
54 		return 0;
55 	default:
56 		ret = readw(host->ioaddr + reg);
57 	}
58 	return ret;
59 }
60 
61 static u32 sdhci_dove_readl(struct sdhci_host *host, int reg)
62 {
63 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
64 	struct sdhci_dove_priv *priv = pltfm_host->priv;
65 	u32 ret;
66 
67 	ret = readl(host->ioaddr + reg);
68 
69 	switch (reg) {
70 	case SDHCI_CAPABILITIES:
71 		/* Mask the support for 3.0V */
72 		ret &= ~SDHCI_CAN_VDD_300;
73 		break;
74 	case SDHCI_PRESENT_STATE:
75 		if (gpio_is_valid(priv->gpio_cd)) {
76 			if (gpio_get_value(priv->gpio_cd) == 0)
77 				ret |= SDHCI_CARD_PRESENT;
78 			else
79 				ret &= ~SDHCI_CARD_PRESENT;
80 		}
81 		break;
82 	}
83 	return ret;
84 }
85 
86 static const struct sdhci_ops sdhci_dove_ops = {
87 	.read_w	= sdhci_dove_readw,
88 	.read_l	= sdhci_dove_readl,
89 };
90 
91 static const struct sdhci_pltfm_data sdhci_dove_pdata = {
92 	.ops	= &sdhci_dove_ops,
93 	.quirks	= SDHCI_QUIRK_NO_SIMULT_VDD_AND_POWER |
94 		  SDHCI_QUIRK_NO_BUSY_IRQ |
95 		  SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
96 		  SDHCI_QUIRK_FORCE_DMA |
97 		  SDHCI_QUIRK_NO_HISPD_BIT,
98 };
99 
100 static int sdhci_dove_probe(struct platform_device *pdev)
101 {
102 	struct sdhci_host *host;
103 	struct sdhci_pltfm_host *pltfm_host;
104 	struct sdhci_dove_priv *priv;
105 	int ret;
106 
107 	priv = devm_kzalloc(&pdev->dev, sizeof(struct sdhci_dove_priv),
108 			    GFP_KERNEL);
109 	if (!priv) {
110 		dev_err(&pdev->dev, "unable to allocate private data");
111 		return -ENOMEM;
112 	}
113 
114 	priv->clk = devm_clk_get(&pdev->dev, NULL);
115 
116 	if (pdev->dev.of_node) {
117 		priv->gpio_cd = of_get_named_gpio(pdev->dev.of_node,
118 						  "cd-gpios", 0);
119 	} else {
120 		priv->gpio_cd = -EINVAL;
121 	}
122 
123 	if (gpio_is_valid(priv->gpio_cd)) {
124 		ret = gpio_request(priv->gpio_cd, "sdhci-cd");
125 		if (ret) {
126 			dev_err(&pdev->dev, "card detect gpio request failed: %d\n",
127 				ret);
128 			return ret;
129 		}
130 		gpio_direction_input(priv->gpio_cd);
131 	}
132 
133 	host = sdhci_pltfm_init(pdev, &sdhci_dove_pdata, 0);
134 	if (IS_ERR(host)) {
135 		ret = PTR_ERR(host);
136 		goto err_sdhci_pltfm_init;
137 	}
138 
139 	pltfm_host = sdhci_priv(host);
140 	pltfm_host->priv = priv;
141 
142 	if (!IS_ERR(priv->clk))
143 		clk_prepare_enable(priv->clk);
144 
145 	sdhci_get_of_property(pdev);
146 
147 	ret = sdhci_add_host(host);
148 	if (ret)
149 		goto err_sdhci_add;
150 
151 	/*
152 	 * We must request the IRQ after sdhci_add_host(), as the tasklet only
153 	 * gets setup in sdhci_add_host() and we oops.
154 	 */
155 	if (gpio_is_valid(priv->gpio_cd)) {
156 		ret = request_irq(gpio_to_irq(priv->gpio_cd),
157 				  sdhci_dove_carddetect_irq,
158 				  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
159 				  mmc_hostname(host->mmc), host);
160 		if (ret) {
161 			dev_err(&pdev->dev, "card detect irq request failed: %d\n",
162 				ret);
163 			goto err_request_irq;
164 		}
165 	}
166 
167 	return 0;
168 
169 err_request_irq:
170 	sdhci_remove_host(host, 0);
171 err_sdhci_add:
172 	if (!IS_ERR(priv->clk))
173 		clk_disable_unprepare(priv->clk);
174 	sdhci_pltfm_free(pdev);
175 err_sdhci_pltfm_init:
176 	if (gpio_is_valid(priv->gpio_cd))
177 		gpio_free(priv->gpio_cd);
178 	return ret;
179 }
180 
181 static int sdhci_dove_remove(struct platform_device *pdev)
182 {
183 	struct sdhci_host *host = platform_get_drvdata(pdev);
184 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
185 	struct sdhci_dove_priv *priv = pltfm_host->priv;
186 
187 	sdhci_pltfm_unregister(pdev);
188 
189 	if (gpio_is_valid(priv->gpio_cd)) {
190 		free_irq(gpio_to_irq(priv->gpio_cd), host);
191 		gpio_free(priv->gpio_cd);
192 	}
193 
194 	if (!IS_ERR(priv->clk))
195 		clk_disable_unprepare(priv->clk);
196 
197 	return 0;
198 }
199 
200 static const struct of_device_id sdhci_dove_of_match_table[] = {
201 	{ .compatible = "marvell,dove-sdhci", },
202 	{}
203 };
204 MODULE_DEVICE_TABLE(of, sdhci_dove_of_match_table);
205 
206 static struct platform_driver sdhci_dove_driver = {
207 	.driver		= {
208 		.name	= "sdhci-dove",
209 		.owner	= THIS_MODULE,
210 		.pm	= SDHCI_PLTFM_PMOPS,
211 		.of_match_table = sdhci_dove_of_match_table,
212 	},
213 	.probe		= sdhci_dove_probe,
214 	.remove		= sdhci_dove_remove,
215 };
216 
217 module_platform_driver(sdhci_dove_driver);
218 
219 MODULE_DESCRIPTION("SDHCI driver for Dove");
220 MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>, "
221 	      "Mike Rapoport <mike@compulab.co.il>");
222 MODULE_LICENSE("GPL v2");
223