diff options
| author | AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> | 2026-01-23 21:20:31 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-01-23 21:24:38 +0300 |
| commit | 63cbabb003ba314be113700ca58ec320b6ce2b33 (patch) | |
| tree | 3f2b137a1b0706f726125bff1e4bf285f7a56f33 | |
| parent | 078117963b2c678921c86f2485b0d5baf5b86131 (diff) | |
| download | linux-63cbabb003ba314be113700ca58ec320b6ce2b33.tar.xz | |
spmi: mtk-pmif: Keep spinlock until read is fully done
Move the spin unlocking to after reading the contents of the
PMIF_SWINF_(x)_RDATA_31_0 register in pmif_spmi_read_cmd():
since this is the only register that we can read to get the
data from all of the arbitered busses, a concurrent request
for reading (especially on a busy arbiter) will show a race
condition and a unexpected or corrupted value may be read.
Doing the entire read sequence while spin locked guarantees
that concurrent access to the arbiter doesn't happen.
Fixes: f200fff8d019 ("spmi: mtk-pmif: Serialize PMIF status check and command submission")
Reviewed-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: Chen-Yu Tsai <wenst@chromium.org>
Signed-off-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Fixes: b45b3ccef8c0 ("spmi: mediatek: Add support for MT6873/8192")
Link: https://patch.msgid.link/20260123182039.224314-4-sboyd@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/spmi/spmi-mtk-pmif.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/drivers/spmi/spmi-mtk-pmif.c b/drivers/spmi/spmi-mtk-pmif.c index 68f458587c67..9f416b231ab8 100644 --- a/drivers/spmi/spmi-mtk-pmif.c +++ b/drivers/spmi/spmi-mtk-pmif.c @@ -22,7 +22,7 @@ #define PMIF_CMD_EXT_REG 2 #define PMIF_CMD_EXT_REG_LONG 3 -#define PMIF_DELAY_US 10 +#define PMIF_DELAY_US 2 #define PMIF_TIMEOUT_US (10 * 1000) #define PMIF_CHAN_OFFSET 0x5 @@ -372,7 +372,6 @@ static int pmif_spmi_read_cmd(struct spmi_controller *ctrl, u8 opc, u8 sid, /* Send the command. */ cmd = (opc << 30) | (sid << 24) | ((len - 1) << 16) | addr; pmif_writel(arb, pbus, cmd, inf_reg->ch_send); - raw_spin_unlock_irqrestore(&pbus->lock, flags); /* * Wait for Software Interface FSM state to be WFVLDCLR, @@ -382,13 +381,16 @@ static int pmif_spmi_read_cmd(struct spmi_controller *ctrl, u8 opc, u8 sid, data, GET_SWINF(data) == SWINF_WFVLDCLR, PMIF_DELAY_US, PMIF_TIMEOUT_US); if (ret < 0) { + raw_spin_unlock_irqrestore(&pbus->lock, flags); dev_err(&ctrl->dev, "failed to wait for SWINF_WFVLDCLR\n"); return ret; } data = pmif_readl(arb, pbus, inf_reg->rdata); - memcpy(buf, &data, len); pmif_writel(arb, pbus, 1, inf_reg->ch_rdy); + raw_spin_unlock_irqrestore(&pbus->lock, flags); + + memcpy(buf, &data, len); return 0; } |