From 7f6d869846eca3800bf0a7fe080260bcc6439c2c Mon Sep 17 00:00:00 2001 From: Charles Keepax Date: Mon, 6 Jan 2020 10:28:34 +0000 Subject: [PATCH] mfd: madera: Wait for boot done before accessing any other registers It is advised to wait for the boot done bit to be set before reading any other register, update the driver to respect this. Signed-off-by: Charles Keepax Signed-off-by: Lee Jones --- drivers/mfd/madera-core.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/mfd/madera-core.c b/drivers/mfd/madera-core.c index a8cfadc..a7d50a7 100644 --- a/drivers/mfd/madera-core.c +++ b/drivers/mfd/madera-core.c @@ -199,7 +199,7 @@ EXPORT_SYMBOL_GPL(madera_name_from_type); #define MADERA_BOOT_POLL_INTERVAL_USEC 5000 #define MADERA_BOOT_POLL_TIMEOUT_USEC 25000 -static int madera_wait_for_boot(struct madera *madera) +static int madera_wait_for_boot_noack(struct madera *madera) { ktime_t timeout; unsigned int val = 0; @@ -226,6 +226,13 @@ static int madera_wait_for_boot(struct madera *madera) ret = -ETIMEDOUT; } + return ret; +} + +static int madera_wait_for_boot(struct madera *madera) +{ + int ret = madera_wait_for_boot_noack(madera); + /* * BOOT_DONE defaults to unmasked on boot so we must ack it. * Do this even after a timeout to avoid interrupt storms. @@ -545,6 +552,12 @@ int madera_dev_init(struct madera *madera) regcache_cache_only(madera->regmap, false); regcache_cache_only(madera->regmap_32bit, false); + ret = madera_wait_for_boot_noack(madera); + if (ret) { + dev_err(madera->dev, "Device failed initial boot: %d\n", ret); + goto err_reset; + } + /* * Now we can power up and verify that this is a chip we know about * before we start doing any writes to its registers. @@ -650,7 +663,7 @@ int madera_dev_init(struct madera *madera) ret = madera_wait_for_boot(madera); if (ret) { - dev_err(madera->dev, "Device failed initial boot: %d\n", ret); + dev_err(madera->dev, "Failed to clear boot done: %d\n", ret); goto err_reset; } -- 2.7.4