| Message ID | 20190403124019.8947-7-wsa+renesas@sang-engineering.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | i2c: core: introduce atomic transfers | expand |
Hi Wolfram,
the subject line of this patch
i2c: omap: Add the master_xfer_irqless hook
still contains the old name of the callback '_irqless'. It should be
'_atomic' instead.
On Wed, Apr 03, 2019 at 02:40:13PM +0200, Wolfram Sang wrote:
> Add the master_xfer_irqless hook to enable i2c transactions
Here again. It should be 'master_xfer_atomic'.
> in irq disabled contexts like the poweroff case.
>
> Signed-off-by: Tero Kristo <t-kristo@ti.com>
> Signed-off-by: Keerthy <j-keerthy@ti.com>
> [wsa: simplified code a little: 'timeout = !ret']
> Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
> drivers/i2c/busses/i2c-omap.c | 76 +++++++++++++++++++++++++++++++++++--------
> 1 file changed, 63 insertions(+), 13 deletions(-)
>
snipped
> @@ -648,15 +650,28 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *omap, u8 size, bool is_rx)
> (1000 * omap->speed / 8);
> }
>
> +static void omap_i2c_wait(struct omap_i2c_dev *omap)
> +{
> + u16 stat;
> + u16 mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG);
> + int count = 0;
> +
> + do {
> + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG);
> + count++;
> + } while (!(stat & mask) && count < 5);
> +}
> +
> /*
> * Low level master read/write transaction.
> */
> static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
> - struct i2c_msg *msg, int stop)
> + struct i2c_msg *msg, int stop, bool polling)
Nitpick. In the patches for the other drivers the boolean flag is called
'atomic' and not 'polling'.
> {
> struct omap_i2c_dev *omap = i2c_get_adapdata(adap);
> unsigned long timeout;
> u16 w;
> + int ret;
>
> dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
> msg->addr, msg->len, msg->flags, stop);
sniped
> @@ -1165,14 +1204,25 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
> }
> } while (stat);
>
> - omap_i2c_complete_cmd(omap, err);
> + return err;
> +}
> +
> +static irqreturn_t
> +omap_i2c_isr_thread(int this_irq, void *dev_id)
> +{
> + int ret;
> + struct omap_i2c_dev *omap = dev_id;
> +
> + ret = omap_i2c_xfer_data(omap);
> + if (ret != -EAGAIN)
> + omap_i2c_complete_cmd(omap, ret);
>
> -out:
> return IRQ_HANDLED;
> }
>
> static const struct i2c_algorithm omap_i2c_algo = {
> - .master_xfer = omap_i2c_xfer,
> + .master_xfer = omap_i2c_xfer_irq,
> + .master_xfer_atomic = omap_i2c_xfer_polling,
When consistency with other drivers is a goal, the functions should be
named like:
.master_xfe = omap_i2c_xfer,
.master_xfer_atomic = omap_i2c_xfer_atomic,
The first without a suffix and the second with the '_atomic' suffix.
Kind regards,
Stefan
> the subject line of this patch > > i2c: omap: Add the master_xfer_irqless hook > > still contains the old name of the callback '_irqless'. It should be > '_atomic' instead. > > > On Wed, Apr 03, 2019 at 02:40:13PM +0200, Wolfram Sang wrote: > > Add the master_xfer_irqless hook to enable i2c transactions > > Here again. It should be 'master_xfer_atomic'. Yes, thanks, fixed! > > static int omap_i2c_xfer_msg(struct i2c_adapter *adap, > > - struct i2c_msg *msg, int stop) > > + struct i2c_msg *msg, int stop, bool polling) > > Nitpick. In the patches for the other drivers the boolean flag is called > 'atomic' and not 'polling'. This patch originally is not from me, so I prefer to not change it. Also, I don't want to enforce strict naming within drivers. As long as it is readable, I am fine with it. > > static const struct i2c_algorithm omap_i2c_algo = { > > - .master_xfer = omap_i2c_xfer, > > + .master_xfer = omap_i2c_xfer_irq, > > + .master_xfer_atomic = omap_i2c_xfer_polling, > > When consistency with other drivers is a goal, the functions should be > named like: > > .master_xfe = omap_i2c_xfer, > .master_xfer_atomic = omap_i2c_xfer_atomic, > > The first without a suffix and the second with the '_atomic' suffix. ditto.
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index cd9c65f3d404..faa0394048a0 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -269,6 +269,8 @@ static const u8 reg_map_ip_v2[] = { [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30, }; +static int omap_i2c_xfer_data(struct omap_i2c_dev *omap); + static inline void omap_i2c_write_reg(struct omap_i2c_dev *omap, int reg, u16 val) { @@ -648,15 +650,28 @@ static void omap_i2c_resize_fifo(struct omap_i2c_dev *omap, u8 size, bool is_rx) (1000 * omap->speed / 8); } +static void omap_i2c_wait(struct omap_i2c_dev *omap) +{ + u16 stat; + u16 mask = omap_i2c_read_reg(omap, OMAP_I2C_IE_REG); + int count = 0; + + do { + stat = omap_i2c_read_reg(omap, OMAP_I2C_STAT_REG); + count++; + } while (!(stat & mask) && count < 5); +} + /* * Low level master read/write transaction. */ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, - struct i2c_msg *msg, int stop) + struct i2c_msg *msg, int stop, bool polling) { struct omap_i2c_dev *omap = i2c_get_adapdata(adap); unsigned long timeout; u16 w; + int ret; dev_dbg(omap->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", msg->addr, msg->len, msg->flags, stop); @@ -680,7 +695,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR; omap_i2c_write_reg(omap, OMAP_I2C_BUF_REG, w); - reinit_completion(&omap->cmd_complete); + if (!polling) + reinit_completion(&omap->cmd_complete); omap->cmd_err = 0; w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT; @@ -732,8 +748,18 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, * REVISIT: We should abort the transfer on signals, but the bus goes * into arbitration and we're currently unable to recover from it. */ - timeout = wait_for_completion_timeout(&omap->cmd_complete, - OMAP_I2C_TIMEOUT); + if (!polling) { + timeout = wait_for_completion_timeout(&omap->cmd_complete, + OMAP_I2C_TIMEOUT); + } else { + do { + omap_i2c_wait(omap); + ret = omap_i2c_xfer_data(omap); + } while (ret == -EAGAIN); + + timeout = !ret; + } + if (timeout == 0) { dev_err(omap->dev, "controller timed out\n"); omap_i2c_reset(omap); @@ -772,7 +798,8 @@ static int omap_i2c_xfer_msg(struct i2c_adapter *adap, * to do the work during IRQ processing. */ static int -omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +omap_i2c_xfer_common(struct i2c_adapter *adap, struct i2c_msg msgs[], int num, + bool polling) { struct omap_i2c_dev *omap = i2c_get_adapdata(adap); int i; @@ -794,7 +821,8 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) omap->set_mpu_wkup_lat(omap->dev, omap->latency); for (i = 0; i < num; i++) { - r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1))); + r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)), + polling); if (r != 0) break; } @@ -813,6 +841,18 @@ omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) return r; } +static int +omap_i2c_xfer_irq(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + return omap_i2c_xfer_common(adap, msgs, num, false); +} + +static int +omap_i2c_xfer_polling(struct i2c_adapter *adap, struct i2c_msg msgs[], int num) +{ + return omap_i2c_xfer_common(adap, msgs, num, true); +} + static u32 omap_i2c_func(struct i2c_adapter *adap) { @@ -1035,10 +1075,8 @@ omap_i2c_isr(int irq, void *dev_id) return ret; } -static irqreturn_t -omap_i2c_isr_thread(int this_irq, void *dev_id) +static int omap_i2c_xfer_data(struct omap_i2c_dev *omap) { - struct omap_i2c_dev *omap = dev_id; u16 bits; u16 stat; int err = 0, count = 0; @@ -1056,7 +1094,8 @@ omap_i2c_isr_thread(int this_irq, void *dev_id) if (!stat) { /* my work here is done */ - goto out; + err = -EAGAIN; + break; } dev_dbg(omap->dev, "IRQ (ISR = 0x%04x)\n", stat); @@ -1165,14 +1204,25 @@ omap_i2c_isr_thread(int this_irq, void *dev_id) } } while (stat); - omap_i2c_complete_cmd(omap, err); + return err; +} + +static irqreturn_t +omap_i2c_isr_thread(int this_irq, void *dev_id) +{ + int ret; + struct omap_i2c_dev *omap = dev_id; + + ret = omap_i2c_xfer_data(omap); + if (ret != -EAGAIN) + omap_i2c_complete_cmd(omap, ret); -out: return IRQ_HANDLED; } static const struct i2c_algorithm omap_i2c_algo = { - .master_xfer = omap_i2c_xfer, + .master_xfer = omap_i2c_xfer_irq, + .master_xfer_atomic = omap_i2c_xfer_polling, .functionality = omap_i2c_func, };