From: Amit Kucheria <amit.kucheria@linaro.org>
To: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org,
bjorn.andersson@linaro.org, edubezval@gmail.com,
andy.gross@linaro.org, Daniel Lezcano <daniel.lezcano@linaro.org>,
David Brown <david.brown@linaro.org>,
Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Subject: [PATCHv3 16/23] drivers: thermal: tsens: simplify get_temp_tsens_v2 routine
Date: Wed, 20 Mar 2019 18:47:56 +0530 [thread overview]
Message-ID: <5646f7e3bd90e4644718f380b28c6115c01bcb7a.1553086065.git.amit.kucheria@linaro.org> (raw)
In-Reply-To: <cover.1553086065.git.amit.kucheria@linaro.org>
In-Reply-To: <cover.1553086065.git.amit.kucheria@linaro.org>
The current implementation is based on an algorithm published in the
docs. Instead of reading the temperature thrice w/o any explanation,
improve the algorithm.
This will become the basis for a common get_temp routine in the future.
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
---
drivers/thermal/qcom/tsens-v2.c | 55 ++++++++++-----------------------
1 file changed, 17 insertions(+), 38 deletions(-)
diff --git a/drivers/thermal/qcom/tsens-v2.c b/drivers/thermal/qcom/tsens-v2.c
index f3eb8661cf7a..716d7f827459 100644
--- a/drivers/thermal/qcom/tsens-v2.c
+++ b/drivers/thermal/qcom/tsens-v2.c
@@ -25,58 +25,37 @@
#define TM_Sn_STATUS_OFF 0x00a0
#define TM_TRDY_OFF 0x00e4
-#define LAST_TEMP_MASK 0xfff
-
-static int get_temp_tsens_v2(struct tsens_priv *priv, int id, int *temp)
+static int get_temp_tsens_v2(struct tsens_priv *priv, int i, int *temp)
{
- struct tsens_sensor *s = &priv->sensor[id];
+ struct tsens_sensor *s = &priv->sensor[i];
u32 temp_idx = LAST_TEMP_0 + s->hw_id;
u32 valid_idx = VALID_0 + s->hw_id;
- u32 last_temp = 0, last_temp2 = 0, last_temp3 = 0, valid;
+ u32 last_temp = 0, valid, mask;
int ret;
- ret = regmap_field_read(priv->rf[temp_idx], &last_temp);
- if (ret)
- return ret;
-
ret = regmap_field_read(priv->rf[valid_idx], &valid);
if (ret)
return ret;
-
- if (valid)
- goto done;
-
- /* Try a second time */
- ret = regmap_field_read(priv->rf[valid_idx], &valid);
- if (ret)
- return ret;
- ret = regmap_field_read(priv->rf[temp_idx], &last_temp2);
- if (ret)
- return ret;
- if (valid) {
- last_temp = last_temp2;
- goto done;
+ while (!valid) {
+ /* Valid bit is 0 for 6 AHB clock cycles.
+ * At 19.2MHz, 1 AHB clock is ~60ns.
+ * We should enter this loop very, very rarely.
+ */
+ ndelay(400);
+ ret = regmap_field_read(priv->rf[valid_idx], &valid);
+ if (ret)
+ return ret;
}
- /* Try a third/last time */
- ret = regmap_field_read(priv->rf[valid_idx], &valid);
- if (ret)
- return ret;
- ret = regmap_field_read(priv->rf[temp_idx], &last_temp3);
+ /* Valid bit is set, OK to read the temperature */
+ ret = regmap_field_read(priv->rf[temp_idx], &last_temp);
if (ret)
return ret;
- if (valid) {
- last_temp = last_temp3;
- goto done;
- }
- if (last_temp == last_temp2)
- last_temp = last_temp2;
- else if (last_temp2 == last_temp3)
- last_temp = last_temp3;
-done:
+ mask = GENMASK(priv->fields[LAST_TEMP_0].msb,
+ priv->fields[LAST_TEMP_0].lsb);
/* Convert temperature from deciCelsius to milliCelsius */
- *temp = sign_extend32(last_temp, fls(LAST_TEMP_MASK) - 1) * 100;
+ *temp = sign_extend32(last_temp, fls(mask) - 1) * 100;
return 0;
}
--
2.17.1
next prev parent reply other threads:[~2019-03-20 13:19 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-20 13:17 [PATCHv3 00/23] thermal: tsens: Refactor to use regmap_field Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 01/23] drivers: thermal: tsens: Document the data structures Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 02/23] drivers: thermal: tsens: Rename tsens_data Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 03/23] drivers: thermal: tsens: Rename tsens_device Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 04/23] drivers: thermal: tsens: Rename variable tmdev Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 05/23] drivers: thermal: tsens: Use consistent names for variables Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 06/23] drivers: thermal: tsens: Function prototypes should have argument names Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 07/23] drivers: thermal: tsens: Rename tsens-8916 to prepare to merge with tsens-8974 Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 08/23] drivers: thermal: tsens: Rename constants " Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 09/23] drivers: thermal: tsens: Merge tsens-8974 into tsens-v0_1 Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 10/23] drivers: thermal: tsens: Introduce reg_fields to deal with register description Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 11/23] drivers: thermal: tsens: Save reference to the device pointer and use it Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 12/23] drivers: thermal: tsens: Don't print error message on -EPROBE_DEFER Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 13/23] drivers: thermal: tsens: Add new operation to check if a sensor is enabled Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 14/23] drivers: thermal: tsens: change data type for sensor IDs Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 15/23] drivers: thermal: tsens: Introduce IP-specific max_sensor count Amit Kucheria
2019-03-20 13:17 ` Amit Kucheria [this message]
2019-03-20 13:17 ` [PATCHv3 17/23] drivers: thermal: tsens: Move get_temp_tsens_v2 to allow sharing Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 18/23] drivers: thermal: tsens: Common get_temp() learns to do ADC conversion Amit Kucheria
2019-03-20 13:17 ` [PATCHv3 19/23] dt: thermal: tsens: Add bindings for qcs404 Amit Kucheria
2019-03-20 13:18 ` [PATCHv3 20/23] drivers: thermal: tsens: Add generic support for TSENS v1 IP Amit Kucheria
2019-03-20 13:18 ` [PATCHv3 21/23] arm64: dts: qcom: qcs404: Add tsens controller Amit Kucheria
2019-06-24 10:59 ` Amit Kucheria
2019-03-20 13:18 ` [PATCHv3 22/23] arm64: dts: qcom: qcs404: Add thermal zones for each sensor Amit Kucheria
2019-03-20 13:18 ` [PATCHv3 23/23] drivers: thermal: tsens: Move calibration constants to header file Amit Kucheria
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