diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/i2c/busses/i2c-mt65xx.c | 33 |
1 files changed, 27 insertions, 6 deletions
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 9b86716..dc4aac6 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -132,6 +132,7 @@ struct mtk_i2c_compatible { unsigned char pmic_i2c: 1; unsigned char dcm: 1; unsigned char auto_restart: 1; + unsigned char aux_len_reg: 1; }; struct mtk_i2c { @@ -153,6 +154,7 @@ struct mtk_i2c { enum mtk_trans_op op; u16 timing_reg; u16 high_speed_reg; + unsigned char auto_restart; const struct mtk_i2c_compatible *dev_comp; }; @@ -178,6 +180,7 @@ static const struct mtk_i2c_compatible mt6577_compat = { .pmic_i2c = 0, .dcm = 1, .auto_restart = 0, + .aux_len_reg = 0, }; static const struct mtk_i2c_compatible mt6589_compat = { @@ -185,6 +188,7 @@ static const struct mtk_i2c_compatible mt6589_compat = { .pmic_i2c = 1, .dcm = 0, .auto_restart = 0, + .aux_len_reg = 0, }; static const struct mtk_i2c_compatible mt8173_compat = { @@ -192,6 +196,7 @@ static const struct mtk_i2c_compatible mt8173_compat = { .pmic_i2c = 0, .dcm = 1, .auto_restart = 1, + .aux_len_reg = 1, }; static const struct of_device_id mtk_i2c_of_match[] = { @@ -373,7 +378,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, i2c->irq_stat = 0; - if (i2c->dev_comp->auto_restart) + if (i2c->auto_restart) restart_flag = I2C_RS_TRANSFER; reinit_completion(&i2c->msg_complete); @@ -411,8 +416,14 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, /* Set transfer and transaction len */ if (i2c->op == I2C_MASTER_WRRD) { - writew(msgs->len | ((msgs + 1)->len) << 8, - i2c->base + OFFSET_TRANSFER_LEN); + if (i2c->dev_comp->aux_len_reg) { + writew(msgs->len, i2c->base + OFFSET_TRANSFER_LEN); + writew((msgs + 1)->len, i2c->base + + OFFSET_TRANSFER_LEN_AUX); + } else { + writew(msgs->len | ((msgs + 1)->len) << 8, + i2c->base + OFFSET_TRANSFER_LEN); + } writew(I2C_WRRD_TRANAC_VALUE, i2c->base + OFFSET_TRANSAC_LEN); } else { writew(msgs->len, i2c->base + OFFSET_TRANSFER_LEN); @@ -461,7 +472,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, writel(I2C_DMA_START_EN, i2c->pdmabase + OFFSET_EN); - if (!i2c->dev_comp->auto_restart) { + if (!i2c->auto_restart) { start_reg = I2C_TRANSAC_START; } else { start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG; @@ -518,6 +529,16 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap, if (ret) return ret; + i2c->auto_restart = i2c->dev_comp->auto_restart; + + /* checking if we can skip restart and optimize using WRRD mode */ + if (i2c->auto_restart && num == 2) { + if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) && + msgs[0].addr == msgs[1].addr) { + i2c->auto_restart = 0; + } + } + while (left_num--) { if (!msgs->buf) { dev_dbg(i2c->dev, "data buffer is NULL.\n"); @@ -530,7 +551,7 @@ static int mtk_i2c_transfer(struct i2c_adapter *adap, else i2c->op = I2C_MASTER_WR; - if (!i2c->dev_comp->auto_restart) { + if (!i2c->auto_restart) { if (num > 1) { /* combined two messages into one transaction */ i2c->op = I2C_MASTER_WRRD; @@ -559,7 +580,7 @@ static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id) u16 restart_flag = 0; u16 intr_stat; - if (i2c->dev_comp->auto_restart) + if (i2c->auto_restart) restart_flag = I2C_RS_TRANSFER; intr_stat = readw(i2c->base + OFFSET_INTR_STAT); |