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authorLinus Torvalds <torvalds@linux-foundation.org>2020-11-14 12:25:39 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2020-11-14 12:25:39 -0800
commit7e908b7461ec395293335852485a183c16765303 (patch)
treef71914dd4130e0cee72013e278dc92787c2ec819 /drivers
parent0c0451112b629946c93ed2102b7ae47d4d1dc0bc (diff)
parent60268b0e8258fdea9a3c9f4b51e161c123571db3 (diff)
Merge tag 'hwmon-for-v5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging
Pull hwmon fixes from Guenter Roeck: - Fix potential bufer overflow in pmbus/max20730 driver - Fix locking issue in pmbus core - Fix regression causing timeouts in applesmc driver - Fix RPM calculation in pwm-fan driver - Restrict counter visibility in amd_energy driver * tag 'hwmon-for-v5.10-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging: hwmon: (amd_energy) modify the visibility of the counters hwmon: (applesmc) Re-work SMC comms hwmon: (pwm-fan) Fix RPM calculation hwmon: (pmbus) Add mutex locking for sysfs reads hwmon: (pmbus/max20730) use scnprintf() instead of snprintf()
Diffstat (limited to 'drivers')
-rw-r--r--drivers/hwmon/amd_energy.c2
-rw-r--r--drivers/hwmon/applesmc.c130
-rw-r--r--drivers/hwmon/pmbus/max20730.c26
-rw-r--r--drivers/hwmon/pmbus/pmbus_core.c13
-rw-r--r--drivers/hwmon/pwm-fan.c16
5 files changed, 115 insertions, 72 deletions
diff --git a/drivers/hwmon/amd_energy.c b/drivers/hwmon/amd_energy.c
index d06597303d5a..3197cda7bcd9 100644
--- a/drivers/hwmon/amd_energy.c
+++ b/drivers/hwmon/amd_energy.c
@@ -171,7 +171,7 @@ static umode_t amd_energy_is_visible(const void *_data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
- return 0444;
+ return 0440;
}
static int energy_accumulator(void *p)
diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
index a18887990f4a..79b498f816fe 100644
--- a/drivers/hwmon/applesmc.c
+++ b/drivers/hwmon/applesmc.c
@@ -32,6 +32,7 @@
#include <linux/hwmon.h>
#include <linux/workqueue.h>
#include <linux/err.h>
+#include <linux/bits.h>
/* data port used by Apple SMC */
#define APPLESMC_DATA_PORT 0x300
@@ -42,10 +43,13 @@
#define APPLESMC_MAX_DATA_LENGTH 32
-/* wait up to 128 ms for a status change. */
-#define APPLESMC_MIN_WAIT 0x0010
-#define APPLESMC_RETRY_WAIT 0x0100
-#define APPLESMC_MAX_WAIT 0x20000
+/* Apple SMC status bits */
+#define SMC_STATUS_AWAITING_DATA BIT(0) /* SMC has data waiting to be read */
+#define SMC_STATUS_IB_CLOSED BIT(1) /* Will ignore any input */
+#define SMC_STATUS_BUSY BIT(2) /* Command in progress */
+
+/* Initial wait is 8us */
+#define APPLESMC_MIN_WAIT 0x0008
#define APPLESMC_READ_CMD 0x10
#define APPLESMC_WRITE_CMD 0x11
@@ -151,65 +155,84 @@ static unsigned int key_at_index;
static struct workqueue_struct *applesmc_led_wq;
/*
- * wait_read - Wait for a byte to appear on SMC port. Callers must
- * hold applesmc_lock.
+ * Wait for specific status bits with a mask on the SMC.
+ * Used before all transactions.
+ * This does 10 fast loops of 8us then exponentially backs off for a
+ * minimum total wait of 262ms. Depending on usleep_range this could
+ * run out past 500ms.
*/
-static int wait_read(void)
+
+static int wait_status(u8 val, u8 mask)
{
- unsigned long end = jiffies + (APPLESMC_MAX_WAIT * HZ) / USEC_PER_SEC;
u8 status;
int us;
+ int i;
- for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
- usleep_range(us, us * 16);
+ us = APPLESMC_MIN_WAIT;
+ for (i = 0; i < 24 ; i++) {
status = inb(APPLESMC_CMD_PORT);
- /* read: wait for smc to settle */
- if (status & 0x01)
+ if ((status & mask) == val)
return 0;
- /* timeout: give up */
- if (time_after(jiffies, end))
- break;
+ usleep_range(us, us * 2);
+ if (i > 9)
+ us <<= 1;
}
-
- pr_warn("wait_read() fail: 0x%02x\n", status);
return -EIO;
}
-/*
- * send_byte - Write to SMC port, retrying when necessary. Callers
- * must hold applesmc_lock.
- */
+/* send_byte - Write to SMC data port. Callers must hold applesmc_lock. */
+
static int send_byte(u8 cmd, u16 port)
{
- u8 status;
- int us;
- unsigned long end = jiffies + (APPLESMC_MAX_WAIT * HZ) / USEC_PER_SEC;
+ int status;
+
+ status = wait_status(0, SMC_STATUS_IB_CLOSED);
+ if (status)
+ return status;
+ /*
+ * This needs to be a separate read looking for bit 0x04
+ * after bit 0x02 falls. If consolidated with the wait above
+ * this extra read may not happen if status returns both
+ * simultaneously and this would appear to be required.
+ */
+ status = wait_status(SMC_STATUS_BUSY, SMC_STATUS_BUSY);
+ if (status)
+ return status;
outb(cmd, port);
- for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) {
- usleep_range(us, us * 16);
- status = inb(APPLESMC_CMD_PORT);
- /* write: wait for smc to settle */
- if (status & 0x02)
- continue;
- /* ready: cmd accepted, return */
- if (status & 0x04)
- return 0;
- /* timeout: give up */
- if (time_after(jiffies, end))
- break;
- /* busy: long wait and resend */
- udelay(APPLESMC_RETRY_WAIT);
- outb(cmd, port);
- }
-
- pr_warn("send_byte(0x%02x, 0x%04x) fail: 0x%02x\n", cmd, port, status);
- return -EIO;
+ return 0;
}
+/* send_command - Write a command to the SMC. Callers must hold applesmc_lock. */
+
static int send_command(u8 cmd)
{
- return send_byte(cmd, APPLESMC_CMD_PORT);
+ int ret;
+
+ ret = wait_status(0, SMC_STATUS_IB_CLOSED);
+ if (ret)
+ return ret;
+ outb(cmd, APPLESMC_CMD_PORT);
+ return 0;
+}
+
+/*
+ * Based on logic from the Apple driver. This is issued before any interaction
+ * If busy is stuck high, issue a read command to reset the SMC state machine.
+ * If busy is stuck high after the command then the SMC is jammed.
+ */
+
+static int smc_sane(void)
+{
+ int ret;
+
+ ret = wait_status(0, SMC_STATUS_BUSY);
+ if (!ret)
+ return ret;
+ ret = send_command(APPLESMC_READ_CMD);
+ if (ret)
+ return ret;
+ return wait_status(0, SMC_STATUS_BUSY);
}
static int send_argument(const char *key)
@@ -226,6 +249,11 @@ static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
{
u8 status, data = 0;
int i;
+ int ret;
+
+ ret = smc_sane();
+ if (ret)
+ return ret;
if (send_command(cmd) || send_argument(key)) {
pr_warn("%.4s: read arg fail\n", key);
@@ -239,7 +267,8 @@ static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
}
for (i = 0; i < len; i++) {
- if (wait_read()) {
+ if (wait_status(SMC_STATUS_AWAITING_DATA | SMC_STATUS_BUSY,
+ SMC_STATUS_AWAITING_DATA | SMC_STATUS_BUSY)) {
pr_warn("%.4s: read data[%d] fail\n", key, i);
return -EIO;
}
@@ -250,19 +279,24 @@ static int read_smc(u8 cmd, const char *key, u8 *buffer, u8 len)
for (i = 0; i < 16; i++) {
udelay(APPLESMC_MIN_WAIT);
status = inb(APPLESMC_CMD_PORT);
- if (!(status & 0x01))
+ if (!(status & SMC_STATUS_AWAITING_DATA))
break;
data = inb(APPLESMC_DATA_PORT);
}
if (i)
pr_warn("flushed %d bytes, last value is: %d\n", i, data);
- return 0;
+ return wait_status(0, SMC_STATUS_BUSY);
}
static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
{
int i;
+ int ret;
+
+ ret = smc_sane();
+ if (ret)
+ return ret;
if (send_command(cmd) || send_argument(key)) {
pr_warn("%s: write arg fail\n", key);
@@ -281,7 +315,7 @@ static int write_smc(u8 cmd, const char *key, const u8 *buffer, u8 len)
}
}
- return 0;
+ return wait_status(0, SMC_STATUS_BUSY);
}
static int read_register_count(unsigned int *count)
diff --git a/drivers/hwmon/pmbus/max20730.c b/drivers/hwmon/pmbus/max20730.c
index 57923d72490c..be83b98411c7 100644
--- a/drivers/hwmon/pmbus/max20730.c
+++ b/drivers/hwmon/pmbus/max20730.c
@@ -122,8 +122,8 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
switch (idx) {
case MAX20730_DEBUGFS_VOUT_MIN:
ret = VOLT_FROM_REG(data->mfr_voutmin * 10000);
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d.%d\n",
- ret / 10000, ret % 10000);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d.%d\n",
+ ret / 10000, ret % 10000);
break;
case MAX20730_DEBUGFS_FREQUENCY:
val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_FSW_MASK)
@@ -141,7 +141,7 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
ret = 800;
else
ret = 900;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_PG_DELAY:
val = (data->mfr_devset1 & MAX20730_MFR_DEVSET1_TSTAT_MASK)
@@ -223,7 +223,7 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
case MAX20730_DEBUGFS_OC_PROTECT_MODE:
ret = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_OCPM_MASK)
>> MAX20730_MFR_DEVSET2_OCPM_BIT_POS;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_SS_TIMING:
val = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_SS_MASK)
@@ -241,32 +241,32 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
case MAX20730_DEBUGFS_IMAX:
ret = (data->mfr_devset2 & MAX20730_MFR_DEVSET2_IMAX_MASK)
>> MAX20730_MFR_DEVSET2_IMAX_BIT_POS;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_OPERATION:
ret = i2c_smbus_read_byte_data(psu->client, PMBUS_OPERATION);
if (ret < 0)
return ret;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_ON_OFF_CONFIG:
ret = i2c_smbus_read_byte_data(psu->client, PMBUS_ON_OFF_CONFIG);
if (ret < 0)
return ret;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_SMBALERT_MASK:
ret = i2c_smbus_read_word_data(psu->client,
PMBUS_SMB_ALERT_MASK);
if (ret < 0)
return ret;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_VOUT_MODE:
ret = i2c_smbus_read_byte_data(psu->client, PMBUS_VOUT_MODE);
if (ret < 0)
return ret;
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX, "%d\n", ret);
break;
case MAX20730_DEBUGFS_VOUT_COMMAND:
ret = i2c_smbus_read_word_data(psu->client, PMBUS_VOUT_COMMAND);
@@ -274,8 +274,8 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
return ret;
ret = VOLT_FROM_REG(ret * 10000);
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX,
- "%d.%d\n", ret / 10000, ret % 10000);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX,
+ "%d.%d\n", ret / 10000, ret % 10000);
break;
case MAX20730_DEBUGFS_VOUT_MAX:
ret = i2c_smbus_read_word_data(psu->client, PMBUS_VOUT_MAX);
@@ -283,8 +283,8 @@ static ssize_t max20730_debugfs_read(struct file *file, char __user *buf,
return ret;
ret = VOLT_FROM_REG(ret * 10000);
- len = snprintf(tbuf, DEBUG_FS_DATA_MAX,
- "%d.%d\n", ret / 10000, ret % 10000);
+ len = scnprintf(tbuf, DEBUG_FS_DATA_MAX,
+ "%d.%d\n", ret / 10000, ret % 10000);
break;
default:
len = strlcpy(tbuf, "Invalid\n", DEBUG_FS_DATA_MAX);
diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c
index 170a9f82ca61..b0e2820a2d57 100644
--- a/drivers/hwmon/pmbus/pmbus_core.c
+++ b/drivers/hwmon/pmbus/pmbus_core.c
@@ -941,12 +941,16 @@ static ssize_t pmbus_show_sensor(struct device *dev,
struct i2c_client *client = to_i2c_client(dev->parent);
struct pmbus_sensor *sensor = to_pmbus_sensor(devattr);
struct pmbus_data *data = i2c_get_clientdata(client);
+ ssize_t ret;
+ mutex_lock(&data->update_lock);
pmbus_update_sensor_data(client, sensor);
if (sensor->data < 0)
- return sensor->data;
-
- return snprintf(buf, PAGE_SIZE, "%lld\n", pmbus_reg2data(data, sensor));
+ ret = sensor->data;
+ else
+ ret = snprintf(buf, PAGE_SIZE, "%lld\n", pmbus_reg2data(data, sensor));
+ mutex_unlock(&data->update_lock);
+ return ret;
}
static ssize_t pmbus_set_sensor(struct device *dev,
@@ -2012,8 +2016,11 @@ static ssize_t pmbus_show_samples(struct device *dev,
int val;
struct i2c_client *client = to_i2c_client(dev->parent);
struct pmbus_samples_reg *reg = to_samples_reg(devattr);
+ struct pmbus_data *data = i2c_get_clientdata(client);
+ mutex_lock(&data->update_lock);
val = _pmbus_read_word_data(client, reg->page, 0xff, reg->attr->reg);
+ mutex_unlock(&data->update_lock);
if (val < 0)
return val;
diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
index bdba2143021a..1f63807c0399 100644
--- a/drivers/hwmon/pwm-fan.c
+++ b/drivers/hwmon/pwm-fan.c
@@ -54,16 +54,18 @@ static irqreturn_t pulse_handler(int irq, void *dev_id)
static void sample_timer(struct timer_list *t)
{
struct pwm_fan_ctx *ctx = from_timer(ctx, t, rpm_timer);
+ unsigned int delta = ktime_ms_delta(ktime_get(), ctx->sample_start);
int pulses;
- u64 tmp;
- pulses = atomic_read(&ctx->pulses);
- atomic_sub(pulses, &ctx->pulses);
- tmp = (u64)pulses * ktime_ms_delta(ktime_get(), ctx->sample_start) * 60;
- do_div(tmp, ctx->pulses_per_revolution * 1000);
- ctx->rpm = tmp;
+ if (delta) {
+ pulses = atomic_read(&ctx->pulses);
+ atomic_sub(pulses, &ctx->pulses);
+ ctx->rpm = (unsigned int)(pulses * 1000 * 60) /
+ (ctx->pulses_per_revolution * delta);
+
+ ctx->sample_start = ktime_get();
+ }
- ctx->sample_start = ktime_get();
mod_timer(&ctx->rpm_timer, jiffies + HZ);
}