2 * (C) Copyright 2015 Google, Inc
4 * (C) Copyright 2008-2014 Rockchip Electronics
5 * Peter, Software Engineering, <superpeter.cai@gmail.com>.
7 * SPDX-License-Identifier: GPL-2.0+
16 #include <asm/arch/clock.h>
17 #include <asm/arch/i2c.h>
18 #include <asm/arch/periph.h>
19 #include <dm/pinctrl.h>
20 #include <linux/sizes.h>
22 DECLARE_GLOBAL_DATA_PTR;
25 #define I2C_TIMEOUT_MS 100
26 #define I2C_RETRY_COUNT 3
28 /* rk i2c fifo max transfer bytes */
29 #define RK_I2C_FIFO_SIZE 32
33 struct udevice *pinctrl;
34 struct i2c_regs *regs;
39 static inline void rk_i2c_get_div(int div, int *divh, int *divl)
45 *divh = DIV_ROUND_UP(div, 2);
49 * SCL Divisor = 8 * (CLKDIVL+1 + CLKDIVH+1)
50 * SCL = PCLK / SCLK Divisor
53 static void rk_i2c_set_clk(struct rk_i2c *i2c, uint32_t scl_rate)
58 /* First get i2c rate from pclk */
59 i2c_rate = clk_get_periph_rate(i2c->clk, i2c->id);
61 div = DIV_ROUND_UP(i2c_rate, scl_rate * 8) - 2;
65 rk_i2c_get_div(div, &divh, &divl);
66 writel(I2C_CLKDIV_VAL(divl, divh), &i2c->regs->clkdiv);
68 debug("rk_i2c_set_clk: i2c rate = %d, scl rate = %d\n", i2c_rate,
70 debug("set i2c clk div = %d, divh = %d, divl = %d\n", div, divh, divl);
71 debug("set clk(I2C_CLKDIV: 0x%08x)\n", readl(&i2c->regs->clkdiv));
74 static void rk_i2c_show_regs(struct i2c_regs *regs)
79 debug("i2c_con: 0x%08x\n", readl(®s->con));
80 debug("i2c_clkdiv: 0x%08x\n", readl(®s->clkdiv));
81 debug("i2c_mrxaddr: 0x%08x\n", readl(®s->mrxaddr));
82 debug("i2c_mrxraddR: 0x%08x\n", readl(®s->mrxraddr));
83 debug("i2c_mtxcnt: 0x%08x\n", readl(®s->mtxcnt));
84 debug("i2c_mrxcnt: 0x%08x\n", readl(®s->mrxcnt));
85 debug("i2c_ien: 0x%08x\n", readl(®s->ien));
86 debug("i2c_ipd: 0x%08x\n", readl(®s->ipd));
87 debug("i2c_fcnt: 0x%08x\n", readl(®s->fcnt));
88 for (i = 0; i < 8; i++)
89 debug("i2c_txdata%d: 0x%08x\n", i, readl(®s->txdata[i]));
90 for (i = 0; i < 8; i++)
91 debug("i2c_rxdata%d: 0x%08x\n", i, readl(®s->rxdata[i]));
95 static int rk_i2c_send_start_bit(struct rk_i2c *i2c)
97 struct i2c_regs *regs = i2c->regs;
100 debug("I2c Send Start bit.\n");
101 writel(I2C_IPD_ALL_CLEAN, ®s->ipd);
103 writel(I2C_CON_EN | I2C_CON_START, ®s->con);
104 writel(I2C_STARTIEN, ®s->ien);
106 start = get_timer(0);
108 if (readl(®s->ipd) & I2C_STARTIPD) {
109 writel(I2C_STARTIPD, ®s->ipd);
112 if (get_timer(start) > I2C_TIMEOUT_MS) {
113 debug("I2C Send Start Bit Timeout\n");
114 rk_i2c_show_regs(regs);
123 static int rk_i2c_send_stop_bit(struct rk_i2c *i2c)
125 struct i2c_regs *regs = i2c->regs;
128 debug("I2c Send Stop bit.\n");
129 writel(I2C_IPD_ALL_CLEAN, ®s->ipd);
131 writel(I2C_CON_EN | I2C_CON_STOP, ®s->con);
132 writel(I2C_CON_STOP, ®s->ien);
134 start = get_timer(0);
136 if (readl(®s->ipd) & I2C_STOPIPD) {
137 writel(I2C_STOPIPD, ®s->ipd);
140 if (get_timer(start) > I2C_TIMEOUT_MS) {
141 debug("I2C Send Start Bit Timeout\n");
142 rk_i2c_show_regs(regs);
151 static inline void rk_i2c_disable(struct rk_i2c *i2c)
153 writel(0, &i2c->regs->con);
156 static int rk_i2c_read(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len,
157 uchar *buf, uint b_len)
159 struct i2c_regs *regs = i2c->regs;
161 uint bytes_remain_len = b_len;
162 uint bytes_xferred = 0;
163 uint words_xferred = 0;
170 debug("rk_i2c_read: chip = %d, reg = %d, r_len = %d, b_len = %d\n",
171 chip, reg, r_len, b_len);
173 err = rk_i2c_send_start_bit(i2c);
177 writel(I2C_MRXADDR_SET(1, chip << 1 | 1), ®s->mrxaddr);
179 writel(0, ®s->mrxraddr);
180 } else if (r_len < 4) {
181 writel(I2C_MRXRADDR_SET(r_len, reg), ®s->mrxraddr);
183 debug("I2C Read: addr len %d not supported\n", r_len);
187 while (bytes_remain_len) {
188 if (bytes_remain_len > RK_I2C_FIFO_SIZE) {
189 con = I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TRX);
192 con = I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TRX) |
194 bytes_xferred = bytes_remain_len;
196 words_xferred = DIV_ROUND_UP(bytes_xferred, 4);
198 writel(con, ®s->con);
199 writel(bytes_xferred, ®s->mrxcnt);
200 writel(I2C_MBRFIEN | I2C_NAKRCVIEN, ®s->ien);
202 start = get_timer(0);
204 if (readl(®s->ipd) & I2C_NAKRCVIPD) {
205 writel(I2C_NAKRCVIPD, ®s->ipd);
208 if (readl(®s->ipd) & I2C_MBRFIPD) {
209 writel(I2C_MBRFIPD, ®s->ipd);
212 if (get_timer(start) > I2C_TIMEOUT_MS) {
213 debug("I2C Read Data Timeout\n");
215 rk_i2c_show_regs(regs);
221 for (i = 0; i < words_xferred; i++) {
222 rxdata = readl(®s->rxdata[i]);
223 debug("I2c Read RXDATA[%d] = 0x%x\n", i, rxdata);
224 for (j = 0; j < 4; j++) {
225 if ((i * 4 + j) == bytes_xferred)
227 *pbuf++ = (rxdata >> (j * 8)) & 0xff;
231 bytes_remain_len -= bytes_xferred;
232 debug("I2C Read bytes_remain_len %d\n", bytes_remain_len);
236 rk_i2c_send_stop_bit(i2c);
242 static int rk_i2c_write(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len,
243 uchar *buf, uint b_len)
245 struct i2c_regs *regs = i2c->regs;
248 uint bytes_remain_len = b_len + r_len + 1;
249 uint bytes_xferred = 0;
250 uint words_xferred = 0;
255 debug("rk_i2c_write: chip = %d, reg = %d, r_len = %d, b_len = %d\n",
256 chip, reg, r_len, b_len);
257 err = rk_i2c_send_start_bit(i2c);
261 while (bytes_remain_len) {
262 if (bytes_remain_len > RK_I2C_FIFO_SIZE)
265 bytes_xferred = bytes_remain_len;
266 words_xferred = DIV_ROUND_UP(bytes_xferred, 4);
268 for (i = 0; i < words_xferred; i++) {
270 for (j = 0; j < 4; j++) {
271 if ((i * 4 + j) == bytes_xferred)
274 if (i == 0 && j == 0) {
275 txdata |= (chip << 1);
276 } else if (i == 0 && j <= r_len) {
278 (0xff << ((j - 1) * 8))) << 8;
280 txdata |= (*pbuf++)<<(j * 8);
282 writel(txdata, ®s->txdata[i]);
284 debug("I2c Write TXDATA[%d] = 0x%x\n", i, txdata);
287 writel(I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TX), ®s->con);
288 writel(bytes_xferred, ®s->mtxcnt);
289 writel(I2C_MBTFIEN | I2C_NAKRCVIEN, ®s->ien);
291 start = get_timer(0);
293 if (readl(®s->ipd) & I2C_NAKRCVIPD) {
294 writel(I2C_NAKRCVIPD, ®s->ipd);
297 if (readl(®s->ipd) & I2C_MBTFIPD) {
298 writel(I2C_MBTFIPD, ®s->ipd);
301 if (get_timer(start) > I2C_TIMEOUT_MS) {
302 debug("I2C Write Data Timeout\n");
304 rk_i2c_show_regs(regs);
310 bytes_remain_len -= bytes_xferred;
311 debug("I2C Write bytes_remain_len %d\n", bytes_remain_len);
315 rk_i2c_send_stop_bit(i2c);
321 static int rockchip_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
324 struct rk_i2c *i2c = dev_get_priv(bus);
327 debug("i2c_xfer: %d messages\n", nmsgs);
328 for (; nmsgs > 0; nmsgs--, msg++) {
329 debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
330 if (msg->flags & I2C_M_RD) {
331 ret = rk_i2c_read(i2c, msg->addr, 0, 0, msg->buf,
334 ret = rk_i2c_write(i2c, msg->addr, 0, 0, msg->buf,
338 debug("i2c_write: error sending\n");
346 int rockchip_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
348 struct rk_i2c *i2c = dev_get_priv(bus);
350 rk_i2c_set_clk(i2c, speed);
355 static int rockchip_i2c_probe(struct udevice *bus)
357 struct rk_i2c *i2c = dev_get_priv(bus);
360 ret = uclass_get_device(UCLASS_PINCTRL, 0, &i2c->pinctrl);
363 ret = uclass_get_device(UCLASS_CLK, 0, &i2c->clk);
366 ret = pinctrl_get_periph_id(i2c->pinctrl, bus);
370 i2c->regs = (void *)dev_get_addr(bus);
371 return pinctrl_request(i2c->pinctrl, i2c->id, 0);
374 static const struct dm_i2c_ops rockchip_i2c_ops = {
375 .xfer = rockchip_i2c_xfer,
376 .set_bus_speed = rockchip_i2c_set_bus_speed,
379 static const struct udevice_id rockchip_i2c_ids[] = {
380 { .compatible = "rockchip,rk3288-i2c" },
384 U_BOOT_DRIVER(i2c_rockchip) = {
385 .name = "i2c_rockchip",
387 .of_match = rockchip_i2c_ids,
388 .probe = rockchip_i2c_probe,
389 .priv_auto_alloc_size = sizeof(struct rk_i2c),
390 .ops = &rockchip_i2c_ops,