diff --git a/drivers/mfd/cs42l43.c b/drivers/mfd/cs42l43.c index a0fb2dc6c3b2..ae8fd37afb75 100644 --- a/drivers/mfd/cs42l43.c +++ b/drivers/mfd/cs42l43.c @@ -43,6 +43,9 @@ #define CS42L43_MCU_UPDATE_TIMEOUT_US 500000 #define CS42L43_MCU_UPDATE_RETRIES 5 +#define CS42L43_MCU_ROM_REV 0x2001 +#define CS42L43_MCU_ROM_BIOS_REV 0x0000 + #define CS42L43_MCU_SUPPORTED_REV 0x2105 #define CS42L43_MCU_SHADOW_REGS_REQUIRED_REV 0x2200 #define CS42L43_MCU_SUPPORTED_BIOS_REV 0x0001 @@ -709,6 +712,23 @@ err: complete(&cs42l43->firmware_download); } +static int cs42l43_mcu_is_hw_compatible(struct cs42l43 *cs42l43, + unsigned int mcu_rev, + unsigned int bios_rev) +{ + /* + * The firmware has two revision numbers bringing either of them up to a + * supported version will provide the disable the driver requires. + */ + if (mcu_rev < CS42L43_MCU_SUPPORTED_REV && + bios_rev < CS42L43_MCU_SUPPORTED_BIOS_REV) { + dev_err(cs42l43->dev, "Firmware too old to support disable\n"); + return -EINVAL; + } + + return 0; +} + /* * The process of updating the firmware is split into a series of steps, at the * end of each step a soft reset of the device might be required which will @@ -745,11 +765,10 @@ static int cs42l43_mcu_update_step(struct cs42l43 *cs42l43) ((mcu_rev & CS42L43_FW_SUBMINOR_REV_MASK) >> 8); /* - * The firmware has two revision numbers bringing either of them up to a - * supported version will provide the features the driver requires. + * The firmware has two revision numbers both of them being at the ROM + * revision indicates no patch has been applied. */ - patched = mcu_rev >= CS42L43_MCU_SUPPORTED_REV || - bios_rev >= CS42L43_MCU_SUPPORTED_BIOS_REV; + patched = mcu_rev != CS42L43_MCU_ROM_REV || bios_rev != CS42L43_MCU_ROM_BIOS_REV; /* * Later versions of the firmwware require the driver to access some * features through a set of shadow registers. @@ -794,10 +813,15 @@ static int cs42l43_mcu_update_step(struct cs42l43 *cs42l43) return cs42l43_mcu_stage_2_3(cs42l43, shadow); } case CS42L43_MCU_BOOT_STAGE3: - if (patched) + if (patched) { + ret = cs42l43_mcu_is_hw_compatible(cs42l43, mcu_rev, bios_rev); + if (ret) + return ret; + return cs42l43_mcu_disable(cs42l43); - else + } else { return cs42l43_mcu_stage_3_2(cs42l43); + } case CS42L43_MCU_BOOT_STAGE4: return 0; default: