openwrt/target/linux/bcm27xx/patches-6.6/950-0560-drivers-hwmon-rp1-adc-check-conversion-validity-befo.patch
Álvaro Fernández Rojas 8c405cdccc bcm27xx: add 6.6 kernel patches
The patches were generated from the RPi repo with the following command:
git format-patch v6.6.34..rpi-6.1.y

Some patches needed rebasing and, as usual, the applied and reverted, wireless
drivers, Github workflows, READMEs and defconfigs patches were removed.

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
2024-06-18 18:52:49 +02:00

35 lines
1.1 KiB
Diff

From 78fc5f683ee0e54489fa0022e920d07db237bd78 Mon Sep 17 00:00:00 2001
From: Jonathan Bell <jonathan@raspberrypi.com>
Date: Thu, 4 May 2023 15:48:53 +0100
Subject: [PATCH 0560/1085] drivers: hwmon: rp1-adc: check conversion validity
before supplying value
The SAR ADC architecture may complete a conversion but instability in the
comparator can corrupt the result. Such corruption is signalled in the CS
ERR bit, asserted alongside each conversion result.
Signed-off-by: Jonathan Bell <jonathan@raspberrypi.com>
---
drivers/hwmon/rp1-adc.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)
--- a/drivers/hwmon/rp1-adc.c
+++ b/drivers/hwmon/rp1-adc.c
@@ -97,8 +97,14 @@ static int rp1_adc_read(struct rp1_adc_d
data->base + RP1_ADC_RWTYPE_SET + RP1_ADC_CS);
ret = rp1_adc_ready_wait(data);
- if (!ret)
- *val = readl(data->base + RP1_ADC_RESULT);
+ if (ret)
+ return ret;
+
+ /* Asserted if the completed conversion had a convergence error */
+ if (readl(data->base + RP1_ADC_CS) & RP1_ADC_CS_ERR)
+ return -EIO;
+
+ *val = readl(data->base + RP1_ADC_RESULT);
spin_unlock(&data->lock);