libata-core: Document some limits/assumptions about ID_ATA (50a99018) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/ata/libata-core.c

+8 −2

Original line number	Diff line number	Diff line
		@@ -1618,6 +1618,9 @@ static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
		* devices. This function also issues ATA_CMD_INIT_DEV_PARAMS
		* for pre-ATA4 drives.
		*
		* FIXME: ATA_CMD_ID_ATA is optional for early drives and right
		* now we abort if we hit that case.
		*
		* LOCKING:
		* Kernel thread context (may sleep)
		*
		@@ -1745,10 +1748,13 @@ int ata_dev_read_id(struct ata_device dev, unsigned int p_class,
		/*
		* The exact sequence expected by certain pre-ATA4 drives is:
		* SRST RESET
		* IDENTIFY
		* INITIALIZE DEVICE PARAMETERS
		* IDENTIFY (optional in early ATA)
		* INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
		* anything else..
		* Some drives were very specific about that exact sequence.
		*
		* Note that ATA4 says lba is mandatory so the second check
		* shoud never trigger.
		*/
		if (ata_id_major_version(id) < 4 \|\| !ata_id_has_lba(id)) {
		err_mask = ata_dev_init_params(dev, id[3], id[6]);