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13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/slab.h>
16#include <linux/delay.h>
17#include <linux/jiffies.h>
18#include <linux/errno.h>
19#include <linux/i2c.h>
20#include <linux/interrupt.h>
21#include <linux/platform_device.h>
22#include <linux/i2c-algo-pca.h>
23#include <linux/i2c-pca-platform.h>
24#include <linux/gpio.h>
25#include <linux/gpio/consumer.h>
26#include <linux/io.h>
27#include <linux/of.h>
28#include <linux/of_device.h>
29
30#include <asm/irq.h>
31
32struct i2c_pca_pf_data {
33 void __iomem *reg_base;
34 int irq;
35 struct gpio_desc *gpio;
36 wait_queue_head_t wait;
37 struct i2c_adapter adap;
38 struct i2c_algo_pca_data algo_data;
39 unsigned long io_base;
40 unsigned long io_size;
41};
42
43
44
45static int i2c_pca_pf_readbyte8(void *pd, int reg)
46{
47 struct i2c_pca_pf_data *i2c = pd;
48 return ioread8(i2c->reg_base + reg);
49}
50
51static int i2c_pca_pf_readbyte16(void *pd, int reg)
52{
53 struct i2c_pca_pf_data *i2c = pd;
54 return ioread8(i2c->reg_base + reg * 2);
55}
56
57static int i2c_pca_pf_readbyte32(void *pd, int reg)
58{
59 struct i2c_pca_pf_data *i2c = pd;
60 return ioread8(i2c->reg_base + reg * 4);
61}
62
63static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
64{
65 struct i2c_pca_pf_data *i2c = pd;
66 iowrite8(val, i2c->reg_base + reg);
67}
68
69static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
70{
71 struct i2c_pca_pf_data *i2c = pd;
72 iowrite8(val, i2c->reg_base + reg * 2);
73}
74
75static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
76{
77 struct i2c_pca_pf_data *i2c = pd;
78 iowrite8(val, i2c->reg_base + reg * 4);
79}
80
81
82static int i2c_pca_pf_waitforcompletion(void *pd)
83{
84 struct i2c_pca_pf_data *i2c = pd;
85 unsigned long timeout;
86 long ret;
87
88 if (i2c->irq) {
89 ret = wait_event_timeout(i2c->wait,
90 i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
91 & I2C_PCA_CON_SI, i2c->adap.timeout);
92 } else {
93
94 timeout = jiffies + i2c->adap.timeout;
95 do {
96 ret = time_before(jiffies, timeout);
97 if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
98 & I2C_PCA_CON_SI)
99 break;
100 udelay(100);
101 } while (ret);
102 }
103
104 return ret > 0;
105}
106
107static void i2c_pca_pf_dummyreset(void *pd)
108{
109 struct i2c_pca_pf_data *i2c = pd;
110
111 dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
112}
113
114static void i2c_pca_pf_resetchip(void *pd)
115{
116 struct i2c_pca_pf_data *i2c = pd;
117
118 gpiod_set_value(i2c->gpio, 1);
119 ndelay(100);
120 gpiod_set_value(i2c->gpio, 0);
121}
122
123static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
124{
125 struct i2c_pca_pf_data *i2c = dev_id;
126
127 if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
128 return IRQ_NONE;
129
130 wake_up(&i2c->wait);
131
132 return IRQ_HANDLED;
133}
134
135
136static int i2c_pca_pf_probe(struct platform_device *pdev)
137{
138 struct i2c_pca_pf_data *i2c;
139 struct resource *res;
140 struct i2c_pca9564_pf_platform_data *platform_data =
141 dev_get_platdata(&pdev->dev);
142 struct device_node *np = pdev->dev.of_node;
143 int ret = 0;
144 int irq;
145
146 irq = platform_get_irq(pdev, 0);
147
148 if (irq < 0)
149 irq = 0;
150
151 i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
152 if (!i2c)
153 return -ENOMEM;
154
155 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
156 i2c->reg_base = devm_ioremap_resource(&pdev->dev, res);
157 if (IS_ERR(i2c->reg_base))
158 return PTR_ERR(i2c->reg_base);
159
160
161 init_waitqueue_head(&i2c->wait);
162
163 i2c->io_base = res->start;
164 i2c->io_size = resource_size(res);
165 i2c->irq = irq;
166
167 i2c->adap.nr = pdev->id;
168 i2c->adap.owner = THIS_MODULE;
169 snprintf(i2c->adap.name, sizeof(i2c->adap.name),
170 "PCA9564/PCA9665 at 0x%08lx",
171 (unsigned long) res->start);
172 i2c->adap.algo_data = &i2c->algo_data;
173 i2c->adap.dev.parent = &pdev->dev;
174 i2c->adap.dev.of_node = np;
175
176 if (platform_data) {
177 i2c->adap.timeout = platform_data->timeout;
178 i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
179 if (gpio_is_valid(platform_data->gpio)) {
180 ret = devm_gpio_request_one(&pdev->dev,
181 platform_data->gpio,
182 GPIOF_ACTIVE_LOW,
183 i2c->adap.name);
184 if (ret == 0) {
185 i2c->gpio = gpio_to_desc(platform_data->gpio);
186 gpiod_direction_output(i2c->gpio, 0);
187 } else {
188 dev_warn(&pdev->dev, "Registering gpio failed!\n");
189 i2c->gpio = NULL;
190 }
191 }
192 } else if (np) {
193 i2c->adap.timeout = HZ;
194 i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset-gpios", GPIOD_OUT_LOW);
195 if (IS_ERR(i2c->gpio))
196 return PTR_ERR(i2c->gpio);
197 of_property_read_u32_index(np, "clock-frequency", 0,
198 &i2c->algo_data.i2c_clock);
199 } else {
200 i2c->adap.timeout = HZ;
201 i2c->algo_data.i2c_clock = 59000;
202 i2c->gpio = NULL;
203 }
204
205 i2c->algo_data.data = i2c;
206 i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
207 if (i2c->gpio)
208 i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
209 else
210 i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
211
212 switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
213 case IORESOURCE_MEM_32BIT:
214 i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
215 i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
216 break;
217 case IORESOURCE_MEM_16BIT:
218 i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
219 i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
220 break;
221 case IORESOURCE_MEM_8BIT:
222 default:
223 i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
224 i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
225 break;
226 }
227
228 if (irq) {
229 ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
230 IRQF_TRIGGER_FALLING, pdev->name, i2c);
231 if (ret)
232 return ret;
233 }
234
235 ret = i2c_pca_add_numbered_bus(&i2c->adap);
236 if (ret)
237 return ret;
238
239 platform_set_drvdata(pdev, i2c);
240
241 dev_info(&pdev->dev, "registered.\n");
242
243 return 0;
244}
245
246static int i2c_pca_pf_remove(struct platform_device *pdev)
247{
248 struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
249
250 i2c_del_adapter(&i2c->adap);
251
252 return 0;
253}
254
255#ifdef CONFIG_OF
256static const struct of_device_id i2c_pca_of_match_table[] = {
257 { .compatible = "nxp,pca9564" },
258 { .compatible = "nxp,pca9665" },
259 {},
260};
261MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
262#endif
263
264static struct platform_driver i2c_pca_pf_driver = {
265 .probe = i2c_pca_pf_probe,
266 .remove = i2c_pca_pf_remove,
267 .driver = {
268 .name = "i2c-pca-platform",
269 .of_match_table = of_match_ptr(i2c_pca_of_match_table),
270 },
271};
272
273module_platform_driver(i2c_pca_pf_driver);
274
275MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
276MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
277MODULE_LICENSE("GPL");
278
