xref: /openbmc/linux/drivers/mfd/mcp-sa11x0.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  linux/drivers/mfd/mcp-sa11x0.c
4  *
5  *  Copyright (C) 2001-2005 Russell King
6  *
7  *  SA11x0 MCP (Multimedia Communications Port) driver.
8  *
9  *  MCP read/write timeouts from Jordi Colomer, rehacked by rmk.
10  */
11 #include <linux/module.h>
12 #include <linux/io.h>
13 #include <linux/errno.h>
14 #include <linux/kernel.h>
15 #include <linux/delay.h>
16 #include <linux/spinlock.h>
17 #include <linux/platform_device.h>
18 #include <linux/pm.h>
19 #include <linux/mfd/mcp.h>
20 
21 #include <mach/hardware.h>
22 #include <asm/mach-types.h>
23 #include <linux/platform_data/mfd-mcp-sa11x0.h>
24 
25 #define DRIVER_NAME "sa11x0-mcp"
26 
27 struct mcp_sa11x0 {
28 	void __iomem	*base0;
29 	void __iomem	*base1;
30 	u32		mccr0;
31 	u32		mccr1;
32 };
33 
34 /* Register offsets */
35 #define MCCR0(m)	((m)->base0 + 0x00)
36 #define MCDR0(m)	((m)->base0 + 0x08)
37 #define MCDR1(m)	((m)->base0 + 0x0c)
38 #define MCDR2(m)	((m)->base0 + 0x10)
39 #define MCSR(m)		((m)->base0 + 0x18)
40 #define MCCR1(m)	((m)->base1 + 0x00)
41 
42 #define priv(mcp)	((struct mcp_sa11x0 *)mcp_priv(mcp))
43 
44 static void
45 mcp_sa11x0_set_telecom_divisor(struct mcp *mcp, unsigned int divisor)
46 {
47 	struct mcp_sa11x0 *m = priv(mcp);
48 
49 	divisor /= 32;
50 
51 	m->mccr0 &= ~0x00007f00;
52 	m->mccr0 |= divisor << 8;
53 	writel_relaxed(m->mccr0, MCCR0(m));
54 }
55 
56 static void
57 mcp_sa11x0_set_audio_divisor(struct mcp *mcp, unsigned int divisor)
58 {
59 	struct mcp_sa11x0 *m = priv(mcp);
60 
61 	divisor /= 32;
62 
63 	m->mccr0 &= ~0x0000007f;
64 	m->mccr0 |= divisor;
65 	writel_relaxed(m->mccr0, MCCR0(m));
66 }
67 
68 /*
69  * Write data to the device.  The bit should be set after 3 subframe
70  * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
71  * We really should try doing something more productive while we
72  * wait.
73  */
74 static void
75 mcp_sa11x0_write(struct mcp *mcp, unsigned int reg, unsigned int val)
76 {
77 	struct mcp_sa11x0 *m = priv(mcp);
78 	int ret = -ETIME;
79 	int i;
80 
81 	writel_relaxed(reg << 17 | MCDR2_Wr | (val & 0xffff), MCDR2(m));
82 
83 	for (i = 0; i < 2; i++) {
84 		udelay(mcp->rw_timeout);
85 		if (readl_relaxed(MCSR(m)) & MCSR_CWC) {
86 			ret = 0;
87 			break;
88 		}
89 	}
90 
91 	if (ret < 0)
92 		printk(KERN_WARNING "mcp: write timed out\n");
93 }
94 
95 /*
96  * Read data from the device.  The bit should be set after 3 subframe
97  * times (each frame is 64 clocks).  We wait a maximum of 6 subframes.
98  * We really should try doing something more productive while we
99  * wait.
100  */
101 static unsigned int
102 mcp_sa11x0_read(struct mcp *mcp, unsigned int reg)
103 {
104 	struct mcp_sa11x0 *m = priv(mcp);
105 	int ret = -ETIME;
106 	int i;
107 
108 	writel_relaxed(reg << 17 | MCDR2_Rd, MCDR2(m));
109 
110 	for (i = 0; i < 2; i++) {
111 		udelay(mcp->rw_timeout);
112 		if (readl_relaxed(MCSR(m)) & MCSR_CRC) {
113 			ret = readl_relaxed(MCDR2(m)) & 0xffff;
114 			break;
115 		}
116 	}
117 
118 	if (ret < 0)
119 		printk(KERN_WARNING "mcp: read timed out\n");
120 
121 	return ret;
122 }
123 
124 static void mcp_sa11x0_enable(struct mcp *mcp)
125 {
126 	struct mcp_sa11x0 *m = priv(mcp);
127 
128 	writel(-1, MCSR(m));
129 	m->mccr0 |= MCCR0_MCE;
130 	writel_relaxed(m->mccr0, MCCR0(m));
131 }
132 
133 static void mcp_sa11x0_disable(struct mcp *mcp)
134 {
135 	struct mcp_sa11x0 *m = priv(mcp);
136 
137 	m->mccr0 &= ~MCCR0_MCE;
138 	writel_relaxed(m->mccr0, MCCR0(m));
139 }
140 
141 /*
142  * Our methods.
143  */
144 static struct mcp_ops mcp_sa11x0 = {
145 	.set_telecom_divisor	= mcp_sa11x0_set_telecom_divisor,
146 	.set_audio_divisor	= mcp_sa11x0_set_audio_divisor,
147 	.reg_write		= mcp_sa11x0_write,
148 	.reg_read		= mcp_sa11x0_read,
149 	.enable			= mcp_sa11x0_enable,
150 	.disable		= mcp_sa11x0_disable,
151 };
152 
153 static int mcp_sa11x0_probe(struct platform_device *dev)
154 {
155 	struct mcp_plat_data *data = dev_get_platdata(&dev->dev);
156 	struct resource *mem0, *mem1;
157 	struct mcp_sa11x0 *m;
158 	struct mcp *mcp;
159 	int ret;
160 
161 	if (!data)
162 		return -ENODEV;
163 
164 	mem0 = platform_get_resource(dev, IORESOURCE_MEM, 0);
165 	mem1 = platform_get_resource(dev, IORESOURCE_MEM, 1);
166 	if (!mem0 || !mem1)
167 		return -ENXIO;
168 
169 	if (!request_mem_region(mem0->start, resource_size(mem0),
170 				DRIVER_NAME)) {
171 		ret = -EBUSY;
172 		goto err_mem0;
173 	}
174 
175 	if (!request_mem_region(mem1->start, resource_size(mem1),
176 				DRIVER_NAME)) {
177 		ret = -EBUSY;
178 		goto err_mem1;
179 	}
180 
181 	mcp = mcp_host_alloc(&dev->dev, sizeof(struct mcp_sa11x0));
182 	if (!mcp) {
183 		ret = -ENOMEM;
184 		goto err_alloc;
185 	}
186 
187 	mcp->owner		= THIS_MODULE;
188 	mcp->ops		= &mcp_sa11x0;
189 	mcp->sclk_rate		= data->sclk_rate;
190 
191 	m = priv(mcp);
192 	m->mccr0 = data->mccr0 | 0x7f7f;
193 	m->mccr1 = data->mccr1;
194 
195 	m->base0 = ioremap(mem0->start, resource_size(mem0));
196 	m->base1 = ioremap(mem1->start, resource_size(mem1));
197 	if (!m->base0 || !m->base1) {
198 		ret = -ENOMEM;
199 		goto err_ioremap;
200 	}
201 
202 	platform_set_drvdata(dev, mcp);
203 
204 	/*
205 	 * Initialise device.  Note that we initially
206 	 * set the sampling rate to minimum.
207 	 */
208 	writel_relaxed(-1, MCSR(m));
209 	writel_relaxed(m->mccr1, MCCR1(m));
210 	writel_relaxed(m->mccr0, MCCR0(m));
211 
212 	/*
213 	 * Calculate the read/write timeout (us) from the bit clock
214 	 * rate.  This is the period for 3 64-bit frames.  Always
215 	 * round this time up.
216 	 */
217 	mcp->rw_timeout = (64 * 3 * 1000000 + mcp->sclk_rate - 1) /
218 			  mcp->sclk_rate;
219 
220 	ret = mcp_host_add(mcp, data->codec_pdata);
221 	if (ret == 0)
222 		return 0;
223 
224  err_ioremap:
225 	iounmap(m->base1);
226 	iounmap(m->base0);
227 	mcp_host_free(mcp);
228  err_alloc:
229 	release_mem_region(mem1->start, resource_size(mem1));
230  err_mem1:
231 	release_mem_region(mem0->start, resource_size(mem0));
232  err_mem0:
233 	return ret;
234 }
235 
236 static int mcp_sa11x0_remove(struct platform_device *dev)
237 {
238 	struct mcp *mcp = platform_get_drvdata(dev);
239 	struct mcp_sa11x0 *m = priv(mcp);
240 	struct resource *mem0, *mem1;
241 
242 	if (m->mccr0 & MCCR0_MCE)
243 		dev_warn(&dev->dev,
244 			 "device left active (missing disable call?)\n");
245 
246 	mem0 = platform_get_resource(dev, IORESOURCE_MEM, 0);
247 	mem1 = platform_get_resource(dev, IORESOURCE_MEM, 1);
248 
249 	mcp_host_del(mcp);
250 	iounmap(m->base1);
251 	iounmap(m->base0);
252 	mcp_host_free(mcp);
253 	release_mem_region(mem1->start, resource_size(mem1));
254 	release_mem_region(mem0->start, resource_size(mem0));
255 
256 	return 0;
257 }
258 
259 #ifdef CONFIG_PM_SLEEP
260 static int mcp_sa11x0_suspend(struct device *dev)
261 {
262 	struct mcp_sa11x0 *m = priv(dev_get_drvdata(dev));
263 
264 	if (m->mccr0 & MCCR0_MCE)
265 		dev_warn(dev, "device left active (missing disable call?)\n");
266 
267 	writel(m->mccr0 & ~MCCR0_MCE, MCCR0(m));
268 
269 	return 0;
270 }
271 
272 static int mcp_sa11x0_resume(struct device *dev)
273 {
274 	struct mcp_sa11x0 *m = priv(dev_get_drvdata(dev));
275 
276 	writel_relaxed(m->mccr1, MCCR1(m));
277 	writel_relaxed(m->mccr0, MCCR0(m));
278 
279 	return 0;
280 }
281 #endif
282 
283 static const struct dev_pm_ops mcp_sa11x0_pm_ops = {
284 #ifdef CONFIG_PM_SLEEP
285 	.suspend = mcp_sa11x0_suspend,
286 	.freeze = mcp_sa11x0_suspend,
287 	.poweroff = mcp_sa11x0_suspend,
288 	.resume_noirq = mcp_sa11x0_resume,
289 	.thaw_noirq = mcp_sa11x0_resume,
290 	.restore_noirq = mcp_sa11x0_resume,
291 #endif
292 };
293 
294 static struct platform_driver mcp_sa11x0_driver = {
295 	.probe		= mcp_sa11x0_probe,
296 	.remove		= mcp_sa11x0_remove,
297 	.driver		= {
298 		.name	= DRIVER_NAME,
299 		.pm	= &mcp_sa11x0_pm_ops,
300 	},
301 };
302 
303 /*
304  * This needs re-working
305  */
306 module_platform_driver(mcp_sa11x0_driver);
307 
308 MODULE_ALIAS("platform:" DRIVER_NAME);
309 MODULE_AUTHOR("Russell King <rmk@arm.linux.org.uk>");
310 MODULE_DESCRIPTION("SA11x0 multimedia communications port driver");
311 MODULE_LICENSE("GPL");
312