Because i2c driver does not generate a stop bit when reading registers of pcf2127
Signed-off-by: Biwen Li biwen.li@nxp.com Signed-off-by: Chuanhua Han chuanhua.han@nxp.com --- drivers/i2c/i2c-uclass.c | 2 ++ drivers/i2c/mxc_i2c.c | 70 +++++++++++++++++++++++++++++++++++----- drivers/rtc/pcf2127.c | 18 ++++++----- include/i2c.h | 2 ++ 4 files changed, 76 insertions(+), 16 deletions(-)
diff --git a/drivers/i2c/i2c-uclass.c b/drivers/i2c/i2c-uclass.c index e47abf1833..18f7364d72 100644 --- a/drivers/i2c/i2c-uclass.c +++ b/drivers/i2c/i2c-uclass.c @@ -141,6 +141,8 @@ int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len) if (len) { ptr->addr = chip->chip_addr; ptr->flags = chip->flags & DM_I2C_CHIP_10BIT ? I2C_M_TEN : 0; + ptr->flags |= chip->flags & DM_I2C_CHIP_RD_NEED_STOP_BIT ? + I2C_M_RD_NEED_STOP_BIT : 0; ptr->flags |= I2C_M_RD; ptr->len = len; ptr->buf = buffer; diff --git a/drivers/i2c/mxc_i2c.c b/drivers/i2c/mxc_i2c.c index 73b9807598..241367bac8 100644 --- a/drivers/i2c/mxc_i2c.c +++ b/drivers/i2c/mxc_i2c.c @@ -962,6 +962,8 @@ static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) int reg_shift = i2c_bus->driver_data & I2C_QUIRK_FLAG ? VF610_I2C_REGSHIFT : IMX_I2C_REGSHIFT; int read_mode; + bool quirk = i2c_bus->driver_data & I2C_QUIRK_FLAG ? true : false; + unsigned int temp;
/* Here address len is set to -1 to not send any address at first. * Otherwise i2c_init_transfer will send the chip address with write @@ -976,6 +978,7 @@ static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) read_mode = -1; /* So it's always different on the first message */ for (; nmsgs > 0; nmsgs--, msg++) { const int msg_is_read = !!(msg->flags & I2C_M_RD); + bool next_is_read = nmsgs > 1 && (msg[1].flags & I2C_M_RD);
debug("i2c_xfer: chip=0x%x, len=0x%x, dir=%c\n", msg->addr, msg->len, msg_is_read ? 'R' : 'W'); @@ -983,13 +986,16 @@ static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) if (msg_is_read != read_mode) { /* Send repeated start if not 1st message */ if (read_mode != -1) { - debug("i2c_xfer: [RSTART]\n"); - ret = readb(base + (I2CR << reg_shift)); - ret |= I2CR_RSTA; - writeb(ret, base + (I2CR << reg_shift)); + if (!(msg[1].flags & I2C_M_RD_NEED_STOP_BIT)) { + debug("i2c_xfer: [RSTART]\n"); + ret = readb(base + (I2CR << reg_shift)); + ret |= I2CR_RSTA; + writeb(ret, base + (I2CR << reg_shift)); + } } debug("i2c_xfer: [ADDR %02x | %c]\n", msg->addr, msg_is_read ? 'R' : 'W'); + ret = tx_byte(i2c_bus, (msg->addr << 1) | msg_is_read); if (ret < 0) { debug("i2c_xfer: [STOP]\n"); @@ -999,16 +1005,64 @@ static int mxc_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs) read_mode = msg_is_read; }
- if (msg->flags & I2C_M_RD) + if (msg->flags & I2C_M_RD) { ret = i2c_read_data(i2c_bus, msg->addr, msg->buf, msg->len, nmsgs == 1 || (msg->flags & I2C_M_STOP)); - else - ret = i2c_write_data(i2c_bus, msg->addr, msg->buf, - msg->len); + if (ret < 0) + break; + continue; + }
+ /* Write message */ + ret = i2c_write_data(i2c_bus, msg->addr, msg->buf, + msg->len); if (ret < 0) break; + + if (!next_is_read) + continue; + + /* Read message following write message */ + if (msg[1].flags & I2C_M_RD_NEED_STOP_BIT) { + /* Generate a stop bit */ + i2c_imx_stop(i2c_bus); + /* Reset i2c slave */ + i2c_force_reset_slave(); + + /* Enable I2C controller */ + if (quirk) + ret = readb(base + (I2CR << reg_shift)) + & I2CR_IDIS; + else + ret = !(readb(base + (I2CR << reg_shift)) + & I2CR_IEN); + if (ret) { + writeb(I2CR_IEN, base + (I2CR << reg_shift)); + /* Wait for controller to be stable */ + udelay(50); + } + + /* Clear interrupt bit */ + writeb(I2SR_IIF_CLEAR, base + (I2SR << reg_shift)); + ret = wait_for_sr_state(i2c_bus, ST_BUS_IDLE); + if (ret < 0) + return ret; + + /* Start I2C transaction */ + temp = readb(base + (I2CR << reg_shift)); + temp |= I2CR_MSTA; + writeb(temp, base + (I2CR << reg_shift)); + + ret = wait_for_sr_state(i2c_bus, ST_BUS_BUSY); + if (ret < 0) + return ret; + + /* Enter transfer mode */ + temp |= I2CR_MTX | I2CR_TX_NO_AK; + writeb(temp, base + (I2CR << reg_shift)); + udelay(50); + } }
if (ret) diff --git a/drivers/rtc/pcf2127.c b/drivers/rtc/pcf2127.c index dcf0340b4d..010c45ecbf 100644 --- a/drivers/rtc/pcf2127.c +++ b/drivers/rtc/pcf2127.c @@ -24,12 +24,9 @@
static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm) { - uchar buf[8]; + uchar buf[7] = {0}; int i = 0, ret;
- /* start register address */ - buf[i++] = PCF2127_REG_SC; - /* hours, minutes and seconds */ buf[i++] = bin2bcd(tm->tm_sec); buf[i++] = bin2bcd(tm->tm_min); @@ -44,7 +41,7 @@ static int pcf2127_rtc_set(struct udevice *dev, const struct rtc_time *tm) buf[i++] = bin2bcd(tm->tm_year % 100);
/* write register's data */ - ret = dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, sizeof(buf)); + ret = dm_i2c_write(dev, PCF2127_REG_SC, buf, i);
return ret; } @@ -54,9 +51,6 @@ static int pcf2127_rtc_get(struct udevice *dev, struct rtc_time *tm) int ret = 0; uchar buf[10] = { PCF2127_REG_CTRL1 };
- ret = dm_i2c_write(dev, PCF2127_REG_CTRL1, buf, 1); - if (ret < 0) - return ret; ret = dm_i2c_read(dev, PCF2127_REG_CTRL1, buf, sizeof(buf)); if (ret < 0) return ret; @@ -90,6 +84,13 @@ static int pcf2127_rtc_reset(struct udevice *dev) return 0; }
+static int pcf2127_probe(struct udevice *dev) +{ + i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_NEED_STOP_BIT); + + return 0; +} + static const struct rtc_ops pcf2127_rtc_ops = { .get = pcf2127_rtc_get, .set = pcf2127_rtc_set, @@ -104,6 +105,7 @@ static const struct udevice_id pcf2127_rtc_ids[] = { U_BOOT_DRIVER(rtc_pcf2127) = { .name = "rtc-pcf2127", .id = UCLASS_RTC, + .probe = pcf2127_probe, .of_match = pcf2127_rtc_ids, .ops = &pcf2127_rtc_ops, }; diff --git a/include/i2c.h b/include/i2c.h index a5c760c711..beaa028349 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -28,6 +28,7 @@ enum dm_i2c_chip_flags { DM_I2C_CHIP_10BIT = 1 << 0, /* Use 10-bit addressing */ DM_I2C_CHIP_RD_ADDRESS = 1 << 1, /* Send address for each read byte */ DM_I2C_CHIP_WR_ADDRESS = 1 << 2, /* Send address for each write byte */ + DM_I2C_CHIP_RD_NEED_STOP_BIT = 1 << 3, /* Need generate stop bit */ };
struct udevice; @@ -87,6 +88,7 @@ enum dm_i2c_msg_flags { I2C_M_IGNORE_NAK = 0x1000, /* continue after NAK */ I2C_M_NO_RD_ACK = 0x0800, /* skip the Ack bit on reads */ I2C_M_RECV_LEN = 0x0400, /* length is first received byte */ + I2C_M_RD_NEED_STOP_BIT = 0x0002, /* need generate stop bit */ };
/**