6.15-stable review patch. If anyone has any objections, please let me know.
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From: André Draszik andre.draszik@linaro.org
[ Upstream commit 67af3cd813695fd3e6432b0849c453250c4685aa ]
ACPM commands that return more than 8 bytes currently don't work correctly, as this driver ignores any such returned bytes.
This is evident in at least acpm_pmic_bulk_read(), where up to 8 registers can be read back and those 8 register values are placed starting at &xfer->rxd[8].
The reason is that xfter->rxlen is initialized with the size of a pointer (8 bytes), rather than the size of the byte array that pointer points to (16 bytes)
Update the code such that we set the number of bytes expected to be the size of the rx buffer.
Note1: While different commands have different lengths rx buffers, we have to specify the same length for all rx buffers since acpm_get_rx() assumes they're all the same length.
Note2: The different commands also have different lengths tx buffers, but before switching the code to use the minimum possible length, some more testing would have to be done to ensure this works correctly in all situations. It seems wiser to just apply this fix here without additional logic changes for now.
Fixes: a88927b534ba ("firmware: add Exynos ACPM protocol driver") Reviewed-by: Tudor Ambarus tudor.ambarus@linaro.org Signed-off-by: André Draszik andre.draszik@linaro.org Link: https://lore.kernel.org/r/20250319-acpm-fixes-v2-1-ac2c1bcf322b@linaro.org Signed-off-by: Krzysztof Kozlowski krzysztof.kozlowski@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/samsung/exynos-acpm-pmic.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/firmware/samsung/exynos-acpm-pmic.c b/drivers/firmware/samsung/exynos-acpm-pmic.c index 85e90d236da21..39b33a356ebd2 100644 --- a/drivers/firmware/samsung/exynos-acpm-pmic.c +++ b/drivers/firmware/samsung/exynos-acpm-pmic.c @@ -43,13 +43,13 @@ static inline u32 acpm_pmic_get_bulk(u32 data, unsigned int i) return (data >> (ACPM_PMIC_BULK_SHIFT * i)) & ACPM_PMIC_BULK_MASK; }
-static void acpm_pmic_set_xfer(struct acpm_xfer *xfer, u32 *cmd, +static void acpm_pmic_set_xfer(struct acpm_xfer *xfer, u32 *cmd, size_t cmdlen, unsigned int acpm_chan_id) { xfer->txd = cmd; xfer->rxd = cmd; - xfer->txlen = sizeof(cmd); - xfer->rxlen = sizeof(cmd); + xfer->txlen = cmdlen; + xfer->rxlen = cmdlen; xfer->acpm_chan_id = acpm_chan_id; }
@@ -71,7 +71,7 @@ int acpm_pmic_read_reg(const struct acpm_handle *handle, int ret;
acpm_pmic_init_read_cmd(cmd, type, reg, chan); - acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id); + acpm_pmic_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id);
ret = acpm_do_xfer(handle, &xfer); if (ret) @@ -104,7 +104,7 @@ int acpm_pmic_bulk_read(const struct acpm_handle *handle, return -EINVAL;
acpm_pmic_init_bulk_read_cmd(cmd, type, reg, chan, count); - acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id); + acpm_pmic_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id);
ret = acpm_do_xfer(handle, &xfer); if (ret) @@ -144,7 +144,7 @@ int acpm_pmic_write_reg(const struct acpm_handle *handle, int ret;
acpm_pmic_init_write_cmd(cmd, type, reg, chan, value); - acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id); + acpm_pmic_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id);
ret = acpm_do_xfer(handle, &xfer); if (ret) @@ -184,7 +184,7 @@ int acpm_pmic_bulk_write(const struct acpm_handle *handle, return -EINVAL;
acpm_pmic_init_bulk_write_cmd(cmd, type, reg, chan, count, buf); - acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id); + acpm_pmic_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id);
ret = acpm_do_xfer(handle, &xfer); if (ret) @@ -214,7 +214,7 @@ int acpm_pmic_update_reg(const struct acpm_handle *handle, int ret;
acpm_pmic_init_update_cmd(cmd, type, reg, chan, value, mask); - acpm_pmic_set_xfer(&xfer, cmd, acpm_chan_id); + acpm_pmic_set_xfer(&xfer, cmd, sizeof(cmd), acpm_chan_id);
ret = acpm_do_xfer(handle, &xfer); if (ret)