diff --git a/drivers/i2c/busses/i2c-lsfs.c b/drivers/i2c/busses/i2c-lsfs.c index 890c63141..0823c2422 100644 --- a/drivers/i2c/busses/i2c-lsfs.c +++ b/drivers/i2c/busses/i2c-lsfs.c @@ -22,6 +22,16 @@ #include #include +// #define I2C_LSFS_DEBUG + +#ifdef I2C_LSFS_DEBUG +#define i2c_lsfs_err dev_err +#define i2c_lsfs_info dev_info +#else +#define i2c_lsfs_err(dev, fmt, ...) +#define i2c_lsfs_info(dev, fmt, ...) +#endif + /* Loongson I2C offset registers */ #define I2C_CR1 0x00 #define I2C_CR2 0x04 @@ -33,6 +43,8 @@ #define I2C_FLTR 0x24 /* Loongson I2C control 1*/ +#define I2C_CR1_SWRST BIT(15) +#define I2C_CR1_RECOVER BIT(14) #define I2C_CR1_POS BIT(11) #define I2C_CR1_ACK BIT(10) #define I2C_CR1_STOP BIT(9) @@ -143,9 +155,9 @@ static int ls_i2c_hw_config(struct ls_i2c_dev *i2c_dev) i2c_set_bits(i2c_dev->base + I2C_CR2, 0x3f); i2c_set_bits(i2c_dev->base + I2C_TRISE, 0x3f); - if (i2c_dev->speed == LS_I2C_SPEED_STANDARD) { + if (i2c_dev->speed == LS_I2C_SPEED_STANDARD) val = DIV_ROUND_UP(i2c_dev->freq, 100000 * 2); - } else { + else { val = DIV_ROUND_UP(i2c_dev->freq, 400000 * 3); /* Select Fast mode */ @@ -197,6 +209,41 @@ static int i2c_wait_EV_signal(struct ls_i2c_dev *i2c_dev, int reg, int mask, int // i2c_wait_EV_signal 返回非 0 时所在对应函数返回 I2C_XFER_TIMEOUT_ERROR #define i2c_wait_EV_signal_t(dev, reg_offset, mask, target) if (i2c_wait_EV_signal(dev, reg_offset, mask, target)) { return -EBUSY;} +/* + * @brief: i2c bus 状态机复位 + * @param: i2c_dev: struct ls_i2c_dev + */ +static void i2c_bus_error_reset_end_of_xfer(struct ls_i2c_dev *i2c_dev) +{ + unsigned char* base; + unsigned int temp; + unsigned int temp_SR1; + unsigned int temp_CR1_mask; + + base = i2c_dev->base; + + temp_SR1 = readl((base + I2C_SR1)); + if (temp_SR1 & I2C_SR1_BERR) + temp_CR1_mask = I2C_CR1_RECOVER; + + // 状态机复位 + temp = readl((base + I2C_CR1)); + temp |= (I2C_CR1_SWRST | temp_CR1_mask); + writel(temp, (base + I2C_CR1)); + + // 错误复位 + temp = readl((base + I2C_SR1)); + temp |= (0xf << 8); + temp ^= (0xf << 8); + writel(temp, (base + I2C_SR1)); + temp = readl((base + I2C_SR1)); + + temp = readl((base + I2C_CR1)); + temp |= (I2C_CR1_SWRST | temp_CR1_mask); + temp ^= (I2C_CR1_SWRST | temp_CR1_mask); + writel(temp, (base + I2C_CR1)); +} + /* * @brief: i2c主模式，接收状态结束时的设置 * @param: base: i2c控制器基地址 @@ -277,12 +324,10 @@ static int i2c_xfer_r_3m(struct ls_i2c_dev *i2c_dev, struct i2c_msg *msg, int is i = 0; remain_read = msg->len; - while (1) - { + while (1) { if (remain_read <= 3) - { break; - } + // 倒数3个字节之前，看 I2C_SR1_RXNE 信号即可，有就读取DR i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_RXNE, 1); i2c_update_read_msg_data(base, msg, i++); @@ -320,7 +365,11 @@ static int i2c_xfer_r(struct ls_i2c_dev *i2c_dev, struct i2c_msg *msg, int is_st temp |= I2C_CR1_ACK; writel(temp, (base + I2C_CR1)); - i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_SB, 1); + ret = i2c_wait_EV_signal(i2c_dev, I2C_SR1, I2C_SR1_SB, 1); + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c read SR1_SB error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_r_end; + } // 把7bit地址左移一位，然后最后1bit设置为1，代表此从地址用于读取 xfer_data = msg->addr; @@ -328,33 +377,38 @@ static int i2c_xfer_r(struct ls_i2c_dev *i2c_dev, struct i2c_msg *msg, int is_st xfer_data |= 1; // bit 0 == 1 read writeb(xfer_data, (base + I2C_DR)); - i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_ADDR, 1); + ret = i2c_wait_EV_signal(i2c_dev, I2C_SR1, I2C_SR1_ADDR, 1); + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c read SR1_ADDR error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_r_end; + } + temp = readl((base + I2C_SR2)); // 针对不同的需要读取的字节数，调用不同的处理函数 if (msg->len == 1) // read 1 byte - { ret = i2c_xfer_r_1(i2c_dev, msg, is_stop); - } else if (msg->len == 2) // read 2 byte - { ret = i2c_xfer_r_2(i2c_dev, msg, is_stop); - } else if (msg->len > 3) // read 3 or more than 3 byte - { ret = i2c_xfer_r_3m(i2c_dev, msg, is_stop); + + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c read xfer data error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_r_end; } +i2c_xfer_r_end: + if (ret) - return ret; - - // 如果需要关闭总线，等待busy信号为0，代表总线总体已经空闲 - if (is_stop) - { - i2c_wait_EV_signal_t(i2c_dev, I2C_SR2, I2C_SR2_BUSY, 0); + i2c_bus_error_reset_end_of_xfer(i2c_dev); + else { + // 如果需要关闭总线，等待busy信号为0，代表总线总体已经空闲 + if (is_stop) + i2c_wait_EV_signal_t(i2c_dev, I2C_SR2, I2C_SR2_BUSY, 0); } - return 0; + return ret; } /* @@ -369,6 +423,7 @@ static int i2c_xfer_w(struct ls_i2c_dev *i2c_dev, struct i2c_msg *msg, int is_st unsigned int temp; int i; unsigned char xfer_data; + int ret; base = i2c_dev->base; @@ -377,46 +432,64 @@ static int i2c_xfer_w(struct ls_i2c_dev *i2c_dev, struct i2c_msg *msg, int is_st temp |= I2C_CR1_START; writel(temp, (base + I2C_CR1)); - i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_SB, 1); + ret = i2c_wait_EV_signal(i2c_dev, I2C_SR1, I2C_SR1_SB, 1); + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c write SR1_SB error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_w_end; + } // 把7bit地址左移一位，然后最后1bit设置为1，代表此从地址用于读取 xfer_data = msg->addr; xfer_data <<= 1; // bit 0 == 0 write writeb(xfer_data, (base + I2C_DR)); - i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_ADDR, 1); + ret = i2c_wait_EV_signal(i2c_dev, I2C_SR1, I2C_SR1_ADDR, 1); + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c write SR1_ADDR error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_w_end; + } + temp = readl((base + I2C_SR2)); // 等待发送数据寄存器为空 - i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_TXE, 1); + ret = i2c_wait_EV_signal(i2c_dev, I2C_SR1, I2C_SR1_TXE, 1); + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c write SR1_TXE error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_w_end; + } i = 0; - while (1) - { + while (1) { if (i == msg->len) - { break; - } xfer_data = msg->buf[i]; ++i; writeb(xfer_data, (base + I2C_DR)); // 等待传送结束 - i2c_wait_EV_signal_t(i2c_dev, I2C_SR1, I2C_SR1_BTF, 1); + ret = i2c_wait_EV_signal(i2c_dev, I2C_SR1, I2C_SR1_BTF, 1); + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c write SR1_BTF error(%d) addr 0x%.2x\n", ret, msg->addr); + goto i2c_xfer_w_end; + } } - if (is_stop) - { - // 关闭总线 - temp = readl((base + I2C_CR1)); - temp |= (I2C_CR1_STOP); - writel(temp, (base + I2C_CR1)); - // 等待busy信号为0，代表总线总体已经空闲 - i2c_wait_EV_signal_t(i2c_dev, I2C_SR2, I2C_SR2_BUSY, 0); +i2c_xfer_w_end: + if (ret) + i2c_bus_error_reset_end_of_xfer(i2c_dev); + else { + if (is_stop) { + // 关闭总线 + temp = readl((base + I2C_CR1)); + temp |= (I2C_CR1_STOP); + writel(temp, (base + I2C_CR1)); + // 等待busy信号为0，代表总线总体已经空闲 + i2c_wait_EV_signal_t(i2c_dev, I2C_SR2, I2C_SR2_BUSY, 0); + } } - return 0; + return ret; } /** @@ -434,22 +507,22 @@ static int ls_i2c_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg msgs[], int int stop; ret = ls_i2c_wait_free_bus(i2c_dev); - if (ret) + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c buf free error(%d)\n", ret); return ret; + } for (i = 0; i < num; i++) { cur_msg = msgs + i; stop = (i == (num - 1)); if (cur_msg->flags & I2C_M_RD) - { ret += i2c_xfer_r(i2c_dev, cur_msg, stop); - } else - { ret += i2c_xfer_w(i2c_dev, cur_msg, stop); + + if (ret) { + i2c_lsfs_err(i2c_dev->dev, "i2c %s error(%d)\n", (cur_msg->flags & I2C_M_RD) ? "read" : "write", ret); // maybe is null } - if (ret) - dev_err(i2c_dev->dev, "i2c %s error(%d)\r\n", (cur_msg->flags & I2C_M_RD) ? "read" : "write", ret); } return (ret < 0) ? ret : num;