From: Brandon Wyman <bjwyman@gmail.com> stable inclusion from stable-5.10.74 commit 42b49f012b6a8c5b012a666971dab6ce38725dff bugzilla: 182986 https://gitee.com/openeuler/kernel/issues/I4I3MG Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit f067d5585cda2de1e47dde914a8a4f151659e0ad ] The bytes for max_power_out from the ibm-cffps devices differ in byte order for some power supplies. The Witherspoon power supply returns the bytes in MSB/LSB order. The Rainier power supply returns the bytes in LSB/MSB order. The Witherspoon power supply uses version cffps1. The Rainier power supply should use version cffps2. If version is cffps1, swap the bytes before output to max_power_out. Tested: Witherspoon before: 3148. Witherspoon after: 3148. Rainier before: 53255. Rainier after: 2000. Signed-off-by: Brandon Wyman <bjwyman@gmail.com> Reviewed-by: Eddie James <eajames@linux.ibm.com> Link: https://lore.kernel.org/r/20210928205051.1222815-1-bjwyman@gmail.com [groeck: Replaced yoda programming] Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Reviewed-by: Weilong Chen <chenweilong@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/hwmon/pmbus/ibm-cffps.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/pmbus/ibm-cffps.c b/drivers/hwmon/pmbus/ibm-cffps.c index 79bc2032dcb2..da261d32450d 100644 --- a/drivers/hwmon/pmbus/ibm-cffps.c +++ b/drivers/hwmon/pmbus/ibm-cffps.c @@ -171,8 +171,14 @@ static ssize_t ibm_cffps_debugfs_read(struct file *file, char __user *buf, cmd = CFFPS_SN_CMD; break; case CFFPS_DEBUGFS_MAX_POWER_OUT: - rc = i2c_smbus_read_word_swapped(psu->client, - CFFPS_MAX_POWER_OUT_CMD); + if (psu->version == cffps1) { + rc = i2c_smbus_read_word_swapped(psu->client, + CFFPS_MAX_POWER_OUT_CMD); + } else { + rc = i2c_smbus_read_word_data(psu->client, + CFFPS_MAX_POWER_OUT_CMD); + } + if (rc < 0) return rc; -- 2.20.1