From 1e27dbe7746f3bcbcf1f9a37f31df4b886e36ce3 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Sat, 23 Jun 2007 17:16:31 -0700 Subject: [PATCH] SM501: Check SM501 ID register on initialisation When binding the driver, check the ID register for a valid identity, in case the SM501 is not functioning correctly. Signed-off-by: Ben Dooks Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/mfd/sm501.c | 14 ++++++++++---- include/linux/sm501-regs.h | 3 +++ 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/mfd/sm501.c b/drivers/mfd/sm501.c index e14d70e0741..8135e4c3bf4 100644 --- a/drivers/mfd/sm501.c +++ b/drivers/mfd/sm501.c @@ -893,6 +893,7 @@ static int sm501_init_dev(struct sm501_devdata *sm) { resource_size_t mem_avail; unsigned long dramctrl; + unsigned long devid; int ret; mutex_init(&sm->clock_lock); @@ -900,13 +901,18 @@ static int sm501_init_dev(struct sm501_devdata *sm) INIT_LIST_HEAD(&sm->devices); - dramctrl = readl(sm->regs + SM501_DRAM_CONTROL); + devid = readl(sm->regs + SM501_DEVICEID); + if ((devid & SM501_DEVICEID_IDMASK) != SM501_DEVICEID_SM501) { + dev_err(sm->dev, "incorrect device id %08lx\n", devid); + return -EINVAL; + } + + dramctrl = readl(sm->regs + SM501_DRAM_CONTROL); mem_avail = sm501_mem_local[(dramctrl >> 13) & 0x7]; - dev_info(sm->dev, "SM501 At %p: Version %08x, %ld Mb, IRQ %d\n", - sm->regs, readl(sm->regs + SM501_DEVICEID), - (unsigned long)mem_avail >> 20, sm->irq); + dev_info(sm->dev, "SM501 At %p: Version %08lx, %ld Mb, IRQ %d\n", + sm->regs, devid, (unsigned long)mem_avail >> 20, sm->irq); sm501_dump_gate(sm); diff --git a/include/linux/sm501-regs.h b/include/linux/sm501-regs.h index 8b4ecf02f9d..014e73b31fc 100644 --- a/include/linux/sm501-regs.h +++ b/include/linux/sm501-regs.h @@ -109,6 +109,9 @@ #define SM501_DEVICEID (0x000060) /* 0x050100A0 */ +#define SM501_DEVICEID_SM501 (0x05010000) +#define SM501_DEVICEID_IDMASK (0xffff0000) + #define SM501_PLLCLOCK_COUNT (0x000064) #define SM501_MISC_TIMING (0x000068) #define SM501_CURRENT_SDRAM_CLOCK (0x00006C) -- 2.41.0