| /* |
| * (C) Copyright 2015 Google, Inc |
| * |
| * (C) Copyright 2008-2014 Rockchip Electronics |
| * Peter, Software Engineering, <superpeter.cai@gmail.com>. |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| */ |
| |
| #include <common.h> |
| #include <clk.h> |
| #include <dm.h> |
| #include <errno.h> |
| #include <i2c.h> |
| #include <asm/io.h> |
| #include <asm/arch/clock.h> |
| #include <asm/arch/i2c.h> |
| #include <asm/arch/periph.h> |
| #include <dm/pinctrl.h> |
| #include <linux/sizes.h> |
| |
| DECLARE_GLOBAL_DATA_PTR; |
| |
| /* i2c timerout */ |
| #define I2C_TIMEOUT_MS 100 |
| #define I2C_RETRY_COUNT 3 |
| |
| /* rk i2c fifo max transfer bytes */ |
| #define RK_I2C_FIFO_SIZE 32 |
| |
| struct rk_i2c { |
| struct udevice *clk; |
| struct udevice *pinctrl; |
| struct i2c_regs *regs; |
| unsigned int speed; |
| enum periph_id id; |
| }; |
| |
| static inline void rk_i2c_get_div(int div, int *divh, int *divl) |
| { |
| *divl = div / 2; |
| if (div % 2 == 0) |
| *divh = div / 2; |
| else |
| *divh = DIV_ROUND_UP(div, 2); |
| } |
| |
| /* |
| * SCL Divisor = 8 * (CLKDIVL+1 + CLKDIVH+1) |
| * SCL = PCLK / SCLK Divisor |
| * i2c_rate = PCLK |
| */ |
| static void rk_i2c_set_clk(struct rk_i2c *i2c, uint32_t scl_rate) |
| { |
| uint32_t i2c_rate; |
| int div, divl, divh; |
| |
| /* First get i2c rate from pclk */ |
| i2c_rate = clk_get_periph_rate(i2c->clk, i2c->id); |
| |
| div = DIV_ROUND_UP(i2c_rate, scl_rate * 8) - 2; |
| divh = 0; |
| divl = 0; |
| if (div >= 0) |
| rk_i2c_get_div(div, &divh, &divl); |
| writel(I2C_CLKDIV_VAL(divl, divh), &i2c->regs->clkdiv); |
| |
| debug("rk_i2c_set_clk: i2c rate = %d, scl rate = %d\n", i2c_rate, |
| scl_rate); |
| debug("set i2c clk div = %d, divh = %d, divl = %d\n", div, divh, divl); |
| debug("set clk(I2C_CLKDIV: 0x%08x)\n", readl(&i2c->regs->clkdiv)); |
| } |
| |
| static void rk_i2c_show_regs(struct i2c_regs *regs) |
| { |
| #ifdef DEBUG |
| uint i; |
| |
| debug("i2c_con: 0x%08x\n", readl(®s->con)); |
| debug("i2c_clkdiv: 0x%08x\n", readl(®s->clkdiv)); |
| debug("i2c_mrxaddr: 0x%08x\n", readl(®s->mrxaddr)); |
| debug("i2c_mrxraddR: 0x%08x\n", readl(®s->mrxraddr)); |
| debug("i2c_mtxcnt: 0x%08x\n", readl(®s->mtxcnt)); |
| debug("i2c_mrxcnt: 0x%08x\n", readl(®s->mrxcnt)); |
| debug("i2c_ien: 0x%08x\n", readl(®s->ien)); |
| debug("i2c_ipd: 0x%08x\n", readl(®s->ipd)); |
| debug("i2c_fcnt: 0x%08x\n", readl(®s->fcnt)); |
| for (i = 0; i < 8; i++) |
| debug("i2c_txdata%d: 0x%08x\n", i, readl(®s->txdata[i])); |
| for (i = 0; i < 8; i++) |
| debug("i2c_rxdata%d: 0x%08x\n", i, readl(®s->rxdata[i])); |
| #endif |
| } |
| |
| static int rk_i2c_send_start_bit(struct rk_i2c *i2c) |
| { |
| struct i2c_regs *regs = i2c->regs; |
| ulong start; |
| |
| debug("I2c Send Start bit.\n"); |
| writel(I2C_IPD_ALL_CLEAN, ®s->ipd); |
| |
| writel(I2C_CON_EN | I2C_CON_START, ®s->con); |
| writel(I2C_STARTIEN, ®s->ien); |
| |
| start = get_timer(0); |
| while (1) { |
| if (readl(®s->ipd) & I2C_STARTIPD) { |
| writel(I2C_STARTIPD, ®s->ipd); |
| break; |
| } |
| if (get_timer(start) > I2C_TIMEOUT_MS) { |
| debug("I2C Send Start Bit Timeout\n"); |
| rk_i2c_show_regs(regs); |
| return -ETIMEDOUT; |
| } |
| udelay(1); |
| } |
| |
| return 0; |
| } |
| |
| static int rk_i2c_send_stop_bit(struct rk_i2c *i2c) |
| { |
| struct i2c_regs *regs = i2c->regs; |
| ulong start; |
| |
| debug("I2c Send Stop bit.\n"); |
| writel(I2C_IPD_ALL_CLEAN, ®s->ipd); |
| |
| writel(I2C_CON_EN | I2C_CON_STOP, ®s->con); |
| writel(I2C_CON_STOP, ®s->ien); |
| |
| start = get_timer(0); |
| while (1) { |
| if (readl(®s->ipd) & I2C_STOPIPD) { |
| writel(I2C_STOPIPD, ®s->ipd); |
| break; |
| } |
| if (get_timer(start) > I2C_TIMEOUT_MS) { |
| debug("I2C Send Start Bit Timeout\n"); |
| rk_i2c_show_regs(regs); |
| return -ETIMEDOUT; |
| } |
| udelay(1); |
| } |
| |
| return 0; |
| } |
| |
| static inline void rk_i2c_disable(struct rk_i2c *i2c) |
| { |
| writel(0, &i2c->regs->con); |
| } |
| |
| static int rk_i2c_read(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len, |
| uchar *buf, uint b_len) |
| { |
| struct i2c_regs *regs = i2c->regs; |
| uchar *pbuf = buf; |
| uint bytes_remain_len = b_len; |
| uint bytes_xferred = 0; |
| uint words_xferred = 0; |
| ulong start; |
| uint con = 0; |
| uint rxdata; |
| uint i, j; |
| int err; |
| |
| debug("rk_i2c_read: chip = %d, reg = %d, r_len = %d, b_len = %d\n", |
| chip, reg, r_len, b_len); |
| |
| err = rk_i2c_send_start_bit(i2c); |
| if (err) |
| return err; |
| |
| writel(I2C_MRXADDR_SET(1, chip << 1 | 1), ®s->mrxaddr); |
| if (r_len == 0) { |
| writel(0, ®s->mrxraddr); |
| } else if (r_len < 4) { |
| writel(I2C_MRXRADDR_SET(r_len, reg), ®s->mrxraddr); |
| } else { |
| debug("I2C Read: addr len %d not supported\n", r_len); |
| return -EIO; |
| } |
| |
| while (bytes_remain_len) { |
| if (bytes_remain_len > RK_I2C_FIFO_SIZE) { |
| con = I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TRX); |
| bytes_xferred = 32; |
| } else { |
| con = I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TRX) | |
| I2C_CON_LASTACK; |
| bytes_xferred = bytes_remain_len; |
| } |
| words_xferred = DIV_ROUND_UP(bytes_xferred, 4); |
| |
| writel(con, ®s->con); |
| writel(bytes_xferred, ®s->mrxcnt); |
| writel(I2C_MBRFIEN | I2C_NAKRCVIEN, ®s->ien); |
| |
| start = get_timer(0); |
| while (1) { |
| if (readl(®s->ipd) & I2C_NAKRCVIPD) { |
| writel(I2C_NAKRCVIPD, ®s->ipd); |
| err = -EREMOTEIO; |
| } |
| if (readl(®s->ipd) & I2C_MBRFIPD) { |
| writel(I2C_MBRFIPD, ®s->ipd); |
| break; |
| } |
| if (get_timer(start) > I2C_TIMEOUT_MS) { |
| debug("I2C Read Data Timeout\n"); |
| err = -ETIMEDOUT; |
| rk_i2c_show_regs(regs); |
| goto i2c_exit; |
| } |
| udelay(1); |
| } |
| |
| for (i = 0; i < words_xferred; i++) { |
| rxdata = readl(®s->rxdata[i]); |
| debug("I2c Read RXDATA[%d] = 0x%x\n", i, rxdata); |
| for (j = 0; j < 4; j++) { |
| if ((i * 4 + j) == bytes_xferred) |
| break; |
| *pbuf++ = (rxdata >> (j * 8)) & 0xff; |
| } |
| } |
| |
| bytes_remain_len -= bytes_xferred; |
| debug("I2C Read bytes_remain_len %d\n", bytes_remain_len); |
| } |
| |
| i2c_exit: |
| rk_i2c_send_stop_bit(i2c); |
| rk_i2c_disable(i2c); |
| |
| return err; |
| } |
| |
| static int rk_i2c_write(struct rk_i2c *i2c, uchar chip, uint reg, uint r_len, |
| uchar *buf, uint b_len) |
| { |
| struct i2c_regs *regs = i2c->regs; |
| int err; |
| uchar *pbuf = buf; |
| uint bytes_remain_len = b_len + r_len + 1; |
| uint bytes_xferred = 0; |
| uint words_xferred = 0; |
| ulong start; |
| uint txdata; |
| uint i, j; |
| |
| debug("rk_i2c_write: chip = %d, reg = %d, r_len = %d, b_len = %d\n", |
| chip, reg, r_len, b_len); |
| err = rk_i2c_send_start_bit(i2c); |
| if (err) |
| return err; |
| |
| while (bytes_remain_len) { |
| if (bytes_remain_len > RK_I2C_FIFO_SIZE) |
| bytes_xferred = 32; |
| else |
| bytes_xferred = bytes_remain_len; |
| words_xferred = DIV_ROUND_UP(bytes_xferred, 4); |
| |
| for (i = 0; i < words_xferred; i++) { |
| txdata = 0; |
| for (j = 0; j < 4; j++) { |
| if ((i * 4 + j) == bytes_xferred) |
| break; |
| |
| if (i == 0 && j == 0) { |
| txdata |= (chip << 1); |
| } else if (i == 0 && j <= r_len) { |
| txdata |= (reg & |
| (0xff << ((j - 1) * 8))) << 8; |
| } else { |
| txdata |= (*pbuf++)<<(j * 8); |
| } |
| writel(txdata, ®s->txdata[i]); |
| } |
| debug("I2c Write TXDATA[%d] = 0x%x\n", i, txdata); |
| } |
| |
| writel(I2C_CON_EN | I2C_CON_MOD(I2C_MODE_TX), ®s->con); |
| writel(bytes_xferred, ®s->mtxcnt); |
| writel(I2C_MBTFIEN | I2C_NAKRCVIEN, ®s->ien); |
| |
| start = get_timer(0); |
| while (1) { |
| if (readl(®s->ipd) & I2C_NAKRCVIPD) { |
| writel(I2C_NAKRCVIPD, ®s->ipd); |
| err = -EREMOTEIO; |
| } |
| if (readl(®s->ipd) & I2C_MBTFIPD) { |
| writel(I2C_MBTFIPD, ®s->ipd); |
| break; |
| } |
| if (get_timer(start) > I2C_TIMEOUT_MS) { |
| debug("I2C Write Data Timeout\n"); |
| err = -ETIMEDOUT; |
| rk_i2c_show_regs(regs); |
| goto i2c_exit; |
| } |
| udelay(1); |
| } |
| |
| bytes_remain_len -= bytes_xferred; |
| debug("I2C Write bytes_remain_len %d\n", bytes_remain_len); |
| } |
| |
| i2c_exit: |
| rk_i2c_send_stop_bit(i2c); |
| rk_i2c_disable(i2c); |
| |
| return err; |
| } |
| |
| static int rockchip_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, |
| int nmsgs) |
| { |
| struct rk_i2c *i2c = dev_get_priv(bus); |
| int ret; |
| |
| debug("i2c_xfer: %d messages\n", nmsgs); |
| for (; nmsgs > 0; nmsgs--, msg++) { |
| debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len); |
| if (msg->flags & I2C_M_RD) { |
| ret = rk_i2c_read(i2c, msg->addr, 0, 0, msg->buf, |
| msg->len); |
| } else { |
| ret = rk_i2c_write(i2c, msg->addr, 0, 0, msg->buf, |
| msg->len); |
| } |
| if (ret) { |
| debug("i2c_write: error sending\n"); |
| return -EREMOTEIO; |
| } |
| } |
| |
| return 0; |
| } |
| |
| int rockchip_i2c_set_bus_speed(struct udevice *bus, unsigned int speed) |
| { |
| struct rk_i2c *i2c = dev_get_priv(bus); |
| |
| rk_i2c_set_clk(i2c, speed); |
| |
| return 0; |
| } |
| |
| static int rockchip_i2c_probe(struct udevice *bus) |
| { |
| struct rk_i2c *i2c = dev_get_priv(bus); |
| int ret; |
| |
| ret = uclass_get_device(UCLASS_PINCTRL, 0, &i2c->pinctrl); |
| if (ret) |
| return ret; |
| ret = uclass_get_device(UCLASS_CLK, 0, &i2c->clk); |
| if (ret) |
| return ret; |
| ret = pinctrl_get_periph_id(i2c->pinctrl, bus); |
| if (ret < 0) |
| return ret; |
| i2c->id = ret; |
| i2c->regs = (void *)dev_get_addr(bus); |
| return pinctrl_request(i2c->pinctrl, i2c->id, 0); |
| } |
| |
| static const struct dm_i2c_ops rockchip_i2c_ops = { |
| .xfer = rockchip_i2c_xfer, |
| .set_bus_speed = rockchip_i2c_set_bus_speed, |
| }; |
| |
| static const struct udevice_id rockchip_i2c_ids[] = { |
| { .compatible = "rockchip,rk3288-i2c" }, |
| { } |
| }; |
| |
| U_BOOT_DRIVER(i2c_rockchip) = { |
| .name = "i2c_rockchip", |
| .id = UCLASS_I2C, |
| .of_match = rockchip_i2c_ids, |
| .probe = rockchip_i2c_probe, |
| .priv_auto_alloc_size = sizeof(struct rk_i2c), |
| .ops = &rockchip_i2c_ops, |
| }; |