Lines Matching full:i2c
3 * I2C bus driver for Conexant Digicolor SoCs
13 #include <linux/i2c.h>
71 static void dc_i2c_cmd(struct dc_i2c *i2c, u8 cmd) in dc_i2c_cmd() argument
73 writeb_relaxed(cmd | II_COMMAND_GO, i2c->regs + II_COMMAND); in dc_i2c_cmd()
86 static void dc_i2c_data(struct dc_i2c *i2c, u8 data) in dc_i2c_data() argument
88 writeb_relaxed(data, i2c->regs + II_DATA); in dc_i2c_data()
91 static void dc_i2c_write_byte(struct dc_i2c *i2c, u8 byte) in dc_i2c_write_byte() argument
93 dc_i2c_data(i2c, byte); in dc_i2c_write_byte()
94 dc_i2c_cmd(i2c, II_CMD_SEND_ACK); in dc_i2c_write_byte()
97 static void dc_i2c_write_buf(struct dc_i2c *i2c) in dc_i2c_write_buf() argument
99 dc_i2c_write_byte(i2c, i2c->msg->buf[i2c->msgbuf_ptr++]); in dc_i2c_write_buf()
102 static void dc_i2c_next_read(struct dc_i2c *i2c) in dc_i2c_next_read() argument
104 bool last = (i2c->msgbuf_ptr + 1 == i2c->msg->len); in dc_i2c_next_read()
106 dc_i2c_cmd(i2c, last ? II_CMD_GET_NOACK : II_CMD_GET_ACK); in dc_i2c_next_read()
109 static void dc_i2c_stop(struct dc_i2c *i2c) in dc_i2c_stop() argument
111 i2c->state = STATE_STOP; in dc_i2c_stop()
112 if (i2c->last) in dc_i2c_stop()
113 dc_i2c_cmd(i2c, II_CMD_STOP); in dc_i2c_stop()
115 complete(&i2c->done); in dc_i2c_stop()
118 static u8 dc_i2c_read_byte(struct dc_i2c *i2c) in dc_i2c_read_byte() argument
120 return readb_relaxed(i2c->regs + II_DATA); in dc_i2c_read_byte()
123 static void dc_i2c_read_buf(struct dc_i2c *i2c) in dc_i2c_read_buf() argument
125 i2c->msg->buf[i2c->msgbuf_ptr++] = dc_i2c_read_byte(i2c); in dc_i2c_read_buf()
126 dc_i2c_next_read(i2c); in dc_i2c_read_buf()
129 static void dc_i2c_set_irq(struct dc_i2c *i2c, int enable) in dc_i2c_set_irq() argument
132 writeb_relaxed(1, i2c->regs + II_INTFLAG_CLEAR); in dc_i2c_set_irq()
133 writeb_relaxed(!!enable, i2c->regs + II_INTENABLE); in dc_i2c_set_irq()
136 static int dc_i2c_cmd_status(struct dc_i2c *i2c) in dc_i2c_cmd_status() argument
138 u8 cmd = readb_relaxed(i2c->regs + II_COMMAND); in dc_i2c_cmd_status()
143 static void dc_i2c_start_msg(struct dc_i2c *i2c, int first) in dc_i2c_start_msg() argument
145 struct i2c_msg *msg = i2c->msg; in dc_i2c_start_msg()
148 i2c->state = STATE_START; in dc_i2c_start_msg()
149 dc_i2c_cmd(i2c, first ? II_CMD_START : II_CMD_RESTART); in dc_i2c_start_msg()
151 i2c->state = STATE_READ; in dc_i2c_start_msg()
152 dc_i2c_next_read(i2c); in dc_i2c_start_msg()
154 i2c->state = STATE_WRITE; in dc_i2c_start_msg()
155 dc_i2c_write_buf(i2c); in dc_i2c_start_msg()
161 struct dc_i2c *i2c = dev_id; in dc_i2c_irq() local
162 int cmd_status = dc_i2c_cmd_status(i2c); in dc_i2c_irq()
165 writeb_relaxed(1, i2c->regs + II_INTFLAG_CLEAR); in dc_i2c_irq()
167 spin_lock(&i2c->lock); in dc_i2c_irq()
171 i2c->error = -EIO; in dc_i2c_irq()
172 complete(&i2c->done); in dc_i2c_irq()
176 switch (i2c->state) { in dc_i2c_irq()
178 addr_cmd = dc_i2c_addr_cmd(i2c->msg); in dc_i2c_irq()
179 dc_i2c_write_byte(i2c, addr_cmd); in dc_i2c_irq()
180 i2c->state = STATE_ADDR; in dc_i2c_irq()
183 if (i2c->msg->flags & I2C_M_RD) { in dc_i2c_irq()
184 dc_i2c_next_read(i2c); in dc_i2c_irq()
185 i2c->state = STATE_READ; in dc_i2c_irq()
188 i2c->state = STATE_WRITE; in dc_i2c_irq()
191 if (i2c->msgbuf_ptr < i2c->msg->len) in dc_i2c_irq()
192 dc_i2c_write_buf(i2c); in dc_i2c_irq()
194 dc_i2c_stop(i2c); in dc_i2c_irq()
197 if (i2c->msgbuf_ptr < i2c->msg->len) in dc_i2c_irq()
198 dc_i2c_read_buf(i2c); in dc_i2c_irq()
200 dc_i2c_stop(i2c); in dc_i2c_irq()
203 i2c->state = STATE_IDLE; in dc_i2c_irq()
204 complete(&i2c->done); in dc_i2c_irq()
209 spin_unlock(&i2c->lock); in dc_i2c_irq()
213 static int dc_i2c_xfer_msg(struct dc_i2c *i2c, struct i2c_msg *msg, int first, in dc_i2c_xfer_msg() argument
219 spin_lock_irqsave(&i2c->lock, flags); in dc_i2c_xfer_msg()
220 i2c->msg = msg; in dc_i2c_xfer_msg()
221 i2c->msgbuf_ptr = 0; in dc_i2c_xfer_msg()
222 i2c->last = last; in dc_i2c_xfer_msg()
223 i2c->error = 0; in dc_i2c_xfer_msg()
225 reinit_completion(&i2c->done); in dc_i2c_xfer_msg()
226 dc_i2c_set_irq(i2c, 1); in dc_i2c_xfer_msg()
227 dc_i2c_start_msg(i2c, first); in dc_i2c_xfer_msg()
228 spin_unlock_irqrestore(&i2c->lock, flags); in dc_i2c_xfer_msg()
230 time_left = wait_for_completion_timeout(&i2c->done, time_left); in dc_i2c_xfer_msg()
231 dc_i2c_set_irq(i2c, 0); in dc_i2c_xfer_msg()
233 i2c->state = STATE_IDLE; in dc_i2c_xfer_msg()
237 if (i2c->error) in dc_i2c_xfer_msg()
238 return i2c->error; in dc_i2c_xfer_msg()
245 struct dc_i2c *i2c = adap->algo_data; in dc_i2c_xfer() local
249 ret = dc_i2c_xfer_msg(i2c, &msgs[i], i == 0, i == num - 1); in dc_i2c_xfer()
257 static int dc_i2c_init_hw(struct dc_i2c *i2c) in dc_i2c_init_hw() argument
259 unsigned long clk_rate = clk_get_rate(i2c->clk); in dc_i2c_init_hw()
262 writeb_relaxed(II_CONTROL_LOCAL_RESET, i2c->regs + II_CONTROL); in dc_i2c_init_hw()
264 writeb_relaxed(0, i2c->regs + II_CONTROL); in dc_i2c_init_hw()
267 clocktime = DIV_ROUND_UP(clk_rate, 64 * i2c->frequency); in dc_i2c_init_hw()
269 dev_err(i2c->dev, "can't set bus speed of %u Hz\n", in dc_i2c_init_hw()
270 i2c->frequency); in dc_i2c_init_hw()
273 writeb_relaxed(clocktime - 1, i2c->regs + II_CLOCKTIME); in dc_i2c_init_hw()
291 struct dc_i2c *i2c; in dc_i2c_probe() local
294 i2c = devm_kzalloc(&pdev->dev, sizeof(struct dc_i2c), GFP_KERNEL); in dc_i2c_probe()
295 if (!i2c) in dc_i2c_probe()
299 &i2c->frequency)) in dc_i2c_probe()
300 i2c->frequency = I2C_MAX_STANDARD_MODE_FREQ; in dc_i2c_probe()
302 i2c->dev = &pdev->dev; in dc_i2c_probe()
303 platform_set_drvdata(pdev, i2c); in dc_i2c_probe()
305 spin_lock_init(&i2c->lock); in dc_i2c_probe()
306 init_completion(&i2c->done); in dc_i2c_probe()
308 i2c->clk = devm_clk_get(&pdev->dev, NULL); in dc_i2c_probe()
309 if (IS_ERR(i2c->clk)) in dc_i2c_probe()
310 return PTR_ERR(i2c->clk); in dc_i2c_probe()
312 i2c->regs = devm_platform_ioremap_resource(pdev, 0); in dc_i2c_probe()
313 if (IS_ERR(i2c->regs)) in dc_i2c_probe()
314 return PTR_ERR(i2c->regs); in dc_i2c_probe()
321 dev_name(&pdev->dev), i2c); in dc_i2c_probe()
325 strscpy(i2c->adap.name, "Conexant Digicolor I2C adapter", in dc_i2c_probe()
326 sizeof(i2c->adap.name)); in dc_i2c_probe()
327 i2c->adap.owner = THIS_MODULE; in dc_i2c_probe()
328 i2c->adap.algo = &dc_i2c_algorithm; in dc_i2c_probe()
329 i2c->adap.dev.parent = &pdev->dev; in dc_i2c_probe()
330 i2c->adap.dev.of_node = np; in dc_i2c_probe()
331 i2c->adap.algo_data = i2c; in dc_i2c_probe()
333 ret = dc_i2c_init_hw(i2c); in dc_i2c_probe()
337 ret = clk_prepare_enable(i2c->clk); in dc_i2c_probe()
341 ret = i2c_add_adapter(&i2c->adap); in dc_i2c_probe()
343 clk_disable_unprepare(i2c->clk); in dc_i2c_probe()
352 struct dc_i2c *i2c = platform_get_drvdata(pdev); in dc_i2c_remove() local
354 i2c_del_adapter(&i2c->adap); in dc_i2c_remove()
355 clk_disable_unprepare(i2c->clk); in dc_i2c_remove()
359 { .compatible = "cnxt,cx92755-i2c" },
368 .name = "digicolor-i2c",
375 MODULE_DESCRIPTION("Conexant Digicolor I2C controller driver");