| Message ID | 1554208560-14817-4-git-send-email-qii.wang@mediatek.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | add i2c support for mt8183 | expand |
On 02/04/2019 14:35, Qii Wang wrote: > When two i2c controllers are internally connected to the same > GPIO pins, the arb clock is needed to ensure that the waveforms > do not interfere with each other. And we also need to enable > the interrupt to find arb lost, old i2c controllers also have > the bit. > > Signed-off-by: Qii Wang <qii.wang@mediatek.com> > Reviewed-by: Nicolas Boichat <drinkcat@chromium.org> > --- > drivers/i2c/busses/i2c-mt65xx.c | 25 ++++++++++++++++++++++--- > 1 file changed, 22 insertions(+), 3 deletions(-) Looks good: Reviewed-by: Matthias Brugger <matthias.bgg@gmail.com> > > diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c > index be36018..1a7235e 100644 > --- a/drivers/i2c/busses/i2c-mt65xx.c > +++ b/drivers/i2c/busses/i2c-mt65xx.c > @@ -35,6 +35,7 @@ > #include <linux/slab.h> > > #define I2C_RS_TRANSFER (1 << 4) > +#define I2C_ARB_LOST (1 << 3) > #define I2C_HS_NACKERR (1 << 2) > #define I2C_ACKERR (1 << 1) > #define I2C_TRANSAC_COMP (1 << 0) > @@ -181,6 +182,7 @@ struct mtk_i2c { > struct clk *clk_main; /* main clock for i2c bus */ > struct clk *clk_dma; /* DMA clock for i2c via DMA */ > struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */ > + struct clk *clk_arb; /* Arbitrator clock for i2c */ > bool have_pmic; /* can use i2c pins from PMIC */ > bool use_push_pull; /* IO config push-pull mode */ > > @@ -299,8 +301,18 @@ static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) > if (ret) > goto err_pmic; > } > + > + if (i2c->clk_arb) { > + ret = clk_prepare_enable(i2c->clk_arb); > + if (ret) > + goto err_arb; > + } > + > return 0; > > +err_arb: > + if (i2c->have_pmic) > + clk_disable_unprepare(i2c->clk_pmic); > err_pmic: > clk_disable_unprepare(i2c->clk_main); > err_main: > @@ -311,6 +323,9 @@ static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) > > static void mtk_i2c_clock_disable(struct mtk_i2c *i2c) > { > + if (i2c->clk_arb) > + clk_disable_unprepare(i2c->clk_arb); > + > if (i2c->have_pmic) > clk_disable_unprepare(i2c->clk_pmic); > > @@ -519,13 +534,13 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, > > /* Clear interrupt status */ > mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | > - I2C_TRANSAC_COMP, OFFSET_INTR_STAT); > + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT); > > mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR); > > /* Enable interrupt */ > mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | > - I2C_TRANSAC_COMP, OFFSET_INTR_MASK); > + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK); > > /* Set transfer and transaction len */ > if (i2c->op == I2C_MASTER_WRRD) { > @@ -659,7 +674,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, > > /* Clear interrupt mask */ > mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | > - I2C_TRANSAC_COMP), OFFSET_INTR_MASK); > + I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK); > > if (i2c->op == I2C_MASTER_WR) { > dma_unmap_single(i2c->dev, wpaddr, > @@ -884,6 +899,10 @@ static int mtk_i2c_probe(struct platform_device *pdev) > return PTR_ERR(i2c->clk_dma); > } > > + i2c->clk_arb = devm_clk_get(&pdev->dev, "arb"); > + if (IS_ERR(i2c->clk_arb)) > + i2c->clk_arb = NULL; > + > clk = i2c->clk_main; > if (i2c->have_pmic) { > i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic"); >
diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index be36018..1a7235e 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -35,6 +35,7 @@ #include <linux/slab.h> #define I2C_RS_TRANSFER (1 << 4) +#define I2C_ARB_LOST (1 << 3) #define I2C_HS_NACKERR (1 << 2) #define I2C_ACKERR (1 << 1) #define I2C_TRANSAC_COMP (1 << 0) @@ -181,6 +182,7 @@ struct mtk_i2c { struct clk *clk_main; /* main clock for i2c bus */ struct clk *clk_dma; /* DMA clock for i2c via DMA */ struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */ + struct clk *clk_arb; /* Arbitrator clock for i2c */ bool have_pmic; /* can use i2c pins from PMIC */ bool use_push_pull; /* IO config push-pull mode */ @@ -299,8 +301,18 @@ static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) if (ret) goto err_pmic; } + + if (i2c->clk_arb) { + ret = clk_prepare_enable(i2c->clk_arb); + if (ret) + goto err_arb; + } + return 0; +err_arb: + if (i2c->have_pmic) + clk_disable_unprepare(i2c->clk_pmic); err_pmic: clk_disable_unprepare(i2c->clk_main); err_main: @@ -311,6 +323,9 @@ static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) static void mtk_i2c_clock_disable(struct mtk_i2c *i2c) { + if (i2c->clk_arb) + clk_disable_unprepare(i2c->clk_arb); + if (i2c->have_pmic) clk_disable_unprepare(i2c->clk_pmic); @@ -519,13 +534,13 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, /* Clear interrupt status */ mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | - I2C_TRANSAC_COMP, OFFSET_INTR_STAT); + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT); mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR); /* Enable interrupt */ mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | - I2C_TRANSAC_COMP, OFFSET_INTR_MASK); + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK); /* Set transfer and transaction len */ if (i2c->op == I2C_MASTER_WRRD) { @@ -659,7 +674,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, /* Clear interrupt mask */ mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | - I2C_TRANSAC_COMP), OFFSET_INTR_MASK); + I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK); if (i2c->op == I2C_MASTER_WR) { dma_unmap_single(i2c->dev, wpaddr, @@ -884,6 +899,10 @@ static int mtk_i2c_probe(struct platform_device *pdev) return PTR_ERR(i2c->clk_dma); } + i2c->clk_arb = devm_clk_get(&pdev->dev, "arb"); + if (IS_ERR(i2c->clk_arb)) + i2c->clk_arb = NULL; + clk = i2c->clk_main; if (i2c->have_pmic) { i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic");