1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Core driver for HTC PASIC3 LED/DS1WM chip.
4 *
5 * Copyright (C) 2006 Philipp Zabel <philipp.zabel@gmail.com>
6 */
7
8 #include <linux/init.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11
12 #include <linux/gpio.h>
13 #include <linux/io.h>
14 #include <linux/irq.h>
15 #include <linux/interrupt.h>
16 #include <linux/mfd/core.h>
17 #include <linux/mfd/ds1wm.h>
18 #include <linux/mfd/htc-pasic3.h>
19 #include <linux/slab.h>
20
21 struct pasic3_data {
22 void __iomem *mapping;
23 unsigned int bus_shift;
24 };
25
26 #define REG_ADDR 5
27 #define REG_DATA 6
28
29 #define READ_MODE 0x80
30
31 /*
32 * write to a secondary register on the PASIC3
33 */
pasic3_write_register(struct device * dev,u32 reg,u8 val)34 void pasic3_write_register(struct device *dev, u32 reg, u8 val)
35 {
36 struct pasic3_data *asic = dev_get_drvdata(dev);
37 int bus_shift = asic->bus_shift;
38 void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
39 void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
40
41 __raw_writeb(~READ_MODE & reg, addr);
42 __raw_writeb(val, data);
43 }
44 EXPORT_SYMBOL(pasic3_write_register); /* for leds-pasic3 */
45
46 /*
47 * read from a secondary register on the PASIC3
48 */
pasic3_read_register(struct device * dev,u32 reg)49 u8 pasic3_read_register(struct device *dev, u32 reg)
50 {
51 struct pasic3_data *asic = dev_get_drvdata(dev);
52 int bus_shift = asic->bus_shift;
53 void __iomem *addr = asic->mapping + (REG_ADDR << bus_shift);
54 void __iomem *data = asic->mapping + (REG_DATA << bus_shift);
55
56 __raw_writeb(READ_MODE | reg, addr);
57 return __raw_readb(data);
58 }
59 EXPORT_SYMBOL(pasic3_read_register); /* for leds-pasic3 */
60
61 /*
62 * LEDs
63 */
64
65 static struct mfd_cell led_cell __initdata = {
66 .name = "leds-pasic3",
67 };
68
69 /*
70 * DS1WM
71 */
72
ds1wm_enable(struct platform_device * pdev)73 static int ds1wm_enable(struct platform_device *pdev)
74 {
75 struct device *dev = pdev->dev.parent;
76 int c;
77
78 c = pasic3_read_register(dev, 0x28);
79 pasic3_write_register(dev, 0x28, c & 0x7f);
80
81 dev_dbg(dev, "DS1WM OWM_EN low (active) %02x\n", c & 0x7f);
82 return 0;
83 }
84
ds1wm_disable(struct platform_device * pdev)85 static int ds1wm_disable(struct platform_device *pdev)
86 {
87 struct device *dev = pdev->dev.parent;
88 int c;
89
90 c = pasic3_read_register(dev, 0x28);
91 pasic3_write_register(dev, 0x28, c | 0x80);
92
93 dev_dbg(dev, "DS1WM OWM_EN high (inactive) %02x\n", c | 0x80);
94 return 0;
95 }
96
97 static struct ds1wm_driver_data ds1wm_pdata = {
98 .active_high = 0,
99 .reset_recover_delay = 1,
100 };
101
102 static struct resource ds1wm_resources[] __initdata = {
103 [0] = {
104 .start = 0,
105 .flags = IORESOURCE_MEM,
106 },
107 [1] = {
108 .start = 0,
109 .end = 0,
110 .flags = IORESOURCE_IRQ,
111 },
112 };
113
114 static const struct mfd_cell ds1wm_cell __initconst = {
115 .name = "ds1wm",
116 .enable = ds1wm_enable,
117 .disable = ds1wm_disable,
118 .platform_data = &ds1wm_pdata,
119 .pdata_size = sizeof(ds1wm_pdata),
120 .num_resources = 2,
121 .resources = ds1wm_resources,
122 };
123
pasic3_probe(struct platform_device * pdev)124 static int __init pasic3_probe(struct platform_device *pdev)
125 {
126 struct pasic3_platform_data *pdata = dev_get_platdata(&pdev->dev);
127 struct device *dev = &pdev->dev;
128 struct pasic3_data *asic;
129 struct resource *r;
130 int ret;
131 int irq = 0;
132
133 r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
134 if (r) {
135 ds1wm_resources[1].flags = IORESOURCE_IRQ | (r->flags &
136 (IORESOURCE_IRQ_HIGHEDGE | IORESOURCE_IRQ_LOWEDGE));
137 irq = r->start;
138 }
139
140 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
141 if (!r)
142 return -ENXIO;
143
144 if (!request_mem_region(r->start, resource_size(r), "pasic3"))
145 return -EBUSY;
146
147 asic = devm_kzalloc(dev, sizeof(struct pasic3_data), GFP_KERNEL);
148 if (!asic)
149 return -ENOMEM;
150
151 platform_set_drvdata(pdev, asic);
152
153 asic->mapping = ioremap(r->start, resource_size(r));
154 if (!asic->mapping) {
155 dev_err(dev, "couldn't ioremap PASIC3\n");
156 return -ENOMEM;
157 }
158
159 /* calculate bus shift from mem resource */
160 asic->bus_shift = (resource_size(r) - 5) >> 3;
161
162 if (pdata && pdata->clock_rate) {
163 ds1wm_pdata.clock_rate = pdata->clock_rate;
164 /* the first 5 PASIC3 registers control the DS1WM */
165 ds1wm_resources[0].end = (5 << asic->bus_shift) - 1;
166 ret = mfd_add_devices(&pdev->dev, pdev->id,
167 &ds1wm_cell, 1, r, irq, NULL);
168 if (ret < 0)
169 dev_warn(dev, "failed to register DS1WM\n");
170 }
171
172 if (pdata && pdata->led_pdata) {
173 led_cell.platform_data = pdata->led_pdata;
174 led_cell.pdata_size = sizeof(struct pasic3_leds_machinfo);
175 ret = mfd_add_devices(&pdev->dev, pdev->id, &led_cell, 1, r,
176 0, NULL);
177 if (ret < 0)
178 dev_warn(dev, "failed to register LED device\n");
179 }
180
181 return 0;
182 }
183
pasic3_remove(struct platform_device * pdev)184 static int pasic3_remove(struct platform_device *pdev)
185 {
186 struct pasic3_data *asic = platform_get_drvdata(pdev);
187 struct resource *r;
188
189 mfd_remove_devices(&pdev->dev);
190
191 iounmap(asic->mapping);
192 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
193 release_mem_region(r->start, resource_size(r));
194 return 0;
195 }
196
197 MODULE_ALIAS("platform:pasic3");
198
199 static struct platform_driver pasic3_driver = {
200 .driver = {
201 .name = "pasic3",
202 },
203 .remove = pasic3_remove,
204 };
205
206 module_platform_driver_probe(pasic3_driver, pasic3_probe);
207
208 MODULE_AUTHOR("Philipp Zabel <philipp.zabel@gmail.com>");
209 MODULE_DESCRIPTION("Core driver for HTC PASIC3");
210 MODULE_LICENSE("GPL");
211