diff options
| author |   Dmitry Osipenko <digetx@gmail.com> | 2020-09-30 01:18:44 +0300 |
|---|---|---|
| committer |   Wolfram Sang <wsa@kernel.org> | 2020-10-05 22:57:39 +0200 |
| commit | 900aed24d3e45353e22f7fc00d6826b87c55761a (patch) | |
| tree | bb336fefbe99c4168b9aa69314db4724c0eabdb9 /drivers/i2c | |
| parent | i2c: testunit: improve documentation (diff) | |
| download | linux-dev-900aed24d3e45353e22f7fc00d6826b87c55761a.tar.xz linux-dev-900aed24d3e45353e22f7fc00d6826b87c55761a.zip | |
i2c: tegra: Make tegra_i2c_flush_fifos() usable in atomic transfer
The tegra_i2c_flush_fifos() shouldn't sleep in atomic transfer and jiffies
are not updating if interrupts are disabled. Let's switch to use iopoll
API helpers for register-polling. The iopoll API provides helpers for both
atomic and non-atomic cases.
Note that this patch doesn't fix any known problem because normally FIFO
is flushed at the time of starting a new transfer.
Reviewed-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index 00d3e4d7a01e..ab88cdd70376 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -470,9 +470,9 @@ err_out: static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) { - unsigned long timeout = jiffies + HZ; - unsigned int offset; - u32 mask, val; + u32 mask, val, offset, reg_offset; + void __iomem *addr; + int err; if (i2c_dev->hw->has_mst_fifo) { mask = I2C_MST_FIFO_CONTROL_TX_FLUSH | @@ -488,12 +488,19 @@ static int tegra_i2c_flush_fifos(struct tegra_i2c_dev *i2c_dev) val |= mask; i2c_writel(i2c_dev, val, offset); - while (i2c_readl(i2c_dev, offset) & mask) { - if (time_after(jiffies, timeout)) { - dev_warn(i2c_dev->dev, "timeout waiting for fifo flush\n"); - return -ETIMEDOUT; - } - usleep_range(1000, 2000); + reg_offset = tegra_i2c_reg_addr(i2c_dev, offset); + addr = i2c_dev->base + reg_offset; + + if (i2c_dev->is_curr_atomic_xfer) + err = readl_relaxed_poll_timeout_atomic(addr, val, !(val & mask), + 1000, 1000000); + else + err = readl_relaxed_poll_timeout(addr, val, !(val & mask), + 1000, 1000000); + + if (err) { + dev_err(i2c_dev->dev, "failed to flush FIFO\n"); + return err; } return 0; } |