diff options
| author | Marek Szyprowski <m.szyprowski@samsung.com> | 2023-10-06 18:08:03 +0300 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2023-10-21 21:45:41 +0300 |
| commit | 445094c8a9fb1ea644aa4e78ba47ccad1cf6c9f5 (patch) | |
| tree | 7ddc9a0eea3d33e6eeb518da1b4a73d9c467d222 /drivers/i2c | |
| parent | 29c9e85d4da2b401b430aa0989932992431745ec (diff) | |
| download | linux-445094c8a9fb1ea644aa4e78ba47ccad1cf6c9f5.tar.xz | |
i2c: exynos5: add support for atomic transfers
Add support for atomic transfers using polling mode with interrupts
intentionally disabled. This removes the warning introduced by commit
63b96983a5dd ("i2c: core: introduce callbacks for atomic transfers")
during system reboot and power-off.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-exynos5.c | 46 |
1 files changed, 44 insertions, 2 deletions
diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c index 2b0b9cdffa86..65cb06ec3804 100644 --- a/drivers/i2c/busses/i2c-exynos5.c +++ b/drivers/i2c/busses/i2c-exynos5.c @@ -194,6 +194,11 @@ struct exynos5_i2c { */ int trans_done; + /* + * Called from atomic context, don't use interrupts. + */ + unsigned int atomic; + /* Controller operating frequency */ unsigned int op_clock; @@ -711,6 +716,22 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop) spin_unlock_irqrestore(&i2c->lock, flags); } +static bool exynos5_i2c_poll_irqs_timeout(struct exynos5_i2c *i2c, + unsigned long timeout) +{ + unsigned long time_left = jiffies + timeout; + + while (time_before(jiffies, time_left) && + !((i2c->trans_done && (i2c->msg->len == i2c->msg_ptr)) || + (i2c->state < 0))) { + while (readl(i2c->regs + HSI2C_INT_ENABLE) & + readl(i2c->regs + HSI2C_INT_STATUS)) + exynos5_i2c_irq(i2c->irq, i2c); + usleep_range(100, 200); + } + return time_before(jiffies, time_left); +} + static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c, struct i2c_msg *msgs, int stop) { @@ -725,8 +746,13 @@ static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c, exynos5_i2c_message_start(i2c, stop); - timeout = wait_for_completion_timeout(&i2c->msg_complete, - EXYNOS5_I2C_TIMEOUT); + if (!i2c->atomic) + timeout = wait_for_completion_timeout(&i2c->msg_complete, + EXYNOS5_I2C_TIMEOUT); + else + timeout = exynos5_i2c_poll_irqs_timeout(i2c, + EXYNOS5_I2C_TIMEOUT); + if (timeout == 0) ret = -ETIMEDOUT; else @@ -777,6 +803,21 @@ err_pclk: return ret ?: num; } +static int exynos5_i2c_xfer_atomic(struct i2c_adapter *adap, + struct i2c_msg *msgs, int num) +{ + struct exynos5_i2c *i2c = adap->algo_data; + int ret; + + disable_irq(i2c->irq); + i2c->atomic = true; + ret = exynos5_i2c_xfer(adap, msgs, num); + i2c->atomic = false; + enable_irq(i2c->irq); + + return ret; +} + static u32 exynos5_i2c_func(struct i2c_adapter *adap) { return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); @@ -784,6 +825,7 @@ static u32 exynos5_i2c_func(struct i2c_adapter *adap) static const struct i2c_algorithm exynos5_i2c_algorithm = { .master_xfer = exynos5_i2c_xfer, + .master_xfer_atomic = exynos5_i2c_xfer_atomic, .functionality = exynos5_i2c_func, }; |