libata: handle early device PIO modes correctly (11e29e21) · Commits · e / devices / android_kernel_fairphone_FP3

drivers/scsi/libata-core.c

+27 −4

Original line number	Diff line number	Diff line
		@@ -1082,6 +1082,31 @@ static inline void ata_dump_id(struct ata_device *dev)
		dev->id[93]);
		}

		/*
		* Compute the PIO modes available for this device. This is not as
		* trivial as it seems if we must consider early devices correctly.
		*
		* FIXME: pre IDE drive timing (do we care ?).
		*/

		static unsigned int ata_pio_modes(struct ata_device *adev)
		{
		u16 modes;

		/* Usual case. Word 53 indicates word 88 is valid */
		if (adev->id[ATA_ID_FIELD_VALID] & (1 << 2)) {
		modes = adev->id[ATA_ID_PIO_MODES] & 0x03;
		modes <<= 3;
		modes \|= 0x7;
		return modes;
		}

		/* If word 88 isn't valid then Word 51 holds the PIO timing number
		for the maximum. Turn it into a mask and return it */
		modes = (2 << (adev->id[ATA_ID_OLD_PIO_MODES] & 0xFF)) - 1 ;
		return modes;
		}

		/**
		* ata_dev_identify - obtain IDENTIFY x DEVICE page
		* @ap: port on which device we wish to probe resides
		@@ -1215,10 +1240,8 @@ static void ata_dev_identify(struct ata_port *ap, unsigned int device)
		xfer_modes = dev->id[ATA_ID_UDMA_MODES];
		if (!xfer_modes)
		xfer_modes = (dev->id[ATA_ID_MWDMA_MODES]) << ATA_SHIFT_MWDMA;
		if (!xfer_modes) {
		xfer_modes = (dev->id[ATA_ID_PIO_MODES]) << (ATA_SHIFT_PIO + 3);
		xfer_modes \|= (0x7 << ATA_SHIFT_PIO);
		}
		if (!xfer_modes)
		xfer_modes = ata_pio_modes(dev);

		ata_dump_id(dev);

+9 −4