From: Benjamin Rood Date: Mon, 2 Nov 2015 20:42:29 +0000 (-0500) Subject: pm80xx: wait a minimum of 500ms before issuing commands to SPCv X-Git-Tag: v4.14-rc1~4218^2^2~96 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=b650a8806e1ba0315fbeda8b45c9e53d73abbb6f;p=platform%2Fkernel%2Flinux-rpi.git pm80xx: wait a minimum of 500ms before issuing commands to SPCv The documentation for the 8070 and 8072 SPCv chip explicitly states that a minimum of 500ms must elapse before issuing commands, otherwise the SPCv may not process them and the firmware may get into an unrecoverable state requiring a reboot. While the Linux guys will probably think this is 'racy', it is called out in the chip documentation and inserting this delay makes power management function properly. Signed-off-by: Benjamin Rood Reviewed-by: Jack Wang Reviewed-by: Hannes Reinecke Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c index 7ce7ea3..d147c41 100644 --- a/drivers/scsi/pm8001/pm8001_init.c +++ b/drivers/scsi/pm8001/pm8001_init.c @@ -1243,6 +1243,19 @@ static int pm8001_pci_resume(struct pci_dev *pdev) for (i = 1; i < pm8001_ha->number_of_intr; i++) PM8001_CHIP_DISP->interrupt_enable(pm8001_ha, i); } + + /* Chip documentation for the 8070 and 8072 SPCv */ + /* states that a 500ms minimum delay is required */ + /* before issuing commands. Otherwise, the firmare */ + /* will enter an unrecoverable state. */ + + if (pm8001_ha->chip_id == chip_8070 || + pm8001_ha->chip_id == chip_8072) { + mdelay(500); + } + + /* Spin up the PHYs */ + pm8001_ha->flags = PM8001F_RUN_TIME; for (i = 0; i < pm8001_ha->chip->n_phy; i++) { pm8001_ha->phy[i].enable_completion = &completion;