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[35.221.147.95]) by smtp.gmail.com with ESMTPSA id 98e67ed59e1d1-306dd10dc40sm1182551a91.9.2025.04.09.02.13.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Apr 2025 02:13:23 -0700 (PDT) From: Hsin-Te Yuan Date: Wed, 09 Apr 2025 09:13:11 +0000 Subject: [PATCH] thermal: sysfs: Return ENODATA instead of EAGAIN for reads Precedence: bulk X-Mailing-List: linux-pm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20250409-temp-v1-1-9a391d8c60fd@chromium.org> X-B4-Tracking: v=1; b=H4sIACc69mcC/6tWKk4tykwtVrJSqFYqSi3LLM7MzwNyDHUUlJIzE vPSU3UzU4B8JSMDI1MDEwNL3ZLU3AJds9SkFEPjxBSDlKQUJaDSgqLUtMwKsDHRsbW1AHYO/vd WAAAA X-Change-ID: 20250409-temp-6ebd13ad0dbd To: "Rafael J. Wysocki" , Daniel Lezcano , Zhang Rui , Lukasz Luba Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, Hsin-Te Yuan X-Mailer: b4 0.15-dev-7be4f When userspace nonblocking reads temperature via sysfs, EAGAIN error returned by thermal driver will confuse user from the usual meaning of EAGAIN, the read would block. Change to throw ENODATA instead of EAGAIN to userspace. Also, ENODATA more accurately reflects that data is not currently available. Signed-off-by: Hsin-Te Yuan --- drivers/thermal/thermal_sysfs.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) --- base-commit: a24588245776dafc227243a01bfbeb8a59bafba9 change-id: 20250409-temp-6ebd13ad0dbd Best regards, diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c index 24b9055a0b6c515b865e0d7e2db1d0de176ff767..3d1713e053dfb867933d95131f1f2491d2ecd07e 100644 --- a/drivers/thermal/thermal_sysfs.c +++ b/drivers/thermal/thermal_sysfs.c @@ -40,8 +40,11 @@ temp_show(struct device *dev, struct device_attribute *attr, char *buf) ret = thermal_zone_get_temp(tz, &temperature); - if (ret) + if (ret) { + if (ret == -EAGAIN) + return -ENODATA; return ret; + } return sprintf(buf, "%d\n", temperature); }