diff options
Diffstat (limited to 'target/linux/bcm27xx/patches-5.4/950-0773-w1_therm-adding-bulk-read-support-to-trigger-multipl.patch')
| -rw-r--r-- | target/linux/bcm27xx/patches-5.4/950-0773-w1_therm-adding-bulk-read-support-to-trigger-multipl.patch | 587 |
1 files changed, 0 insertions, 587 deletions
diff --git a/target/linux/bcm27xx/patches-5.4/950-0773-w1_therm-adding-bulk-read-support-to-trigger-multipl.patch b/target/linux/bcm27xx/patches-5.4/950-0773-w1_therm-adding-bulk-read-support-to-trigger-multipl.patch deleted file mode 100644 index ad641e1e98..0000000000 --- a/target/linux/bcm27xx/patches-5.4/950-0773-w1_therm-adding-bulk-read-support-to-trigger-multipl.patch +++ /dev/null @@ -1,587 +0,0 @@ -From e6585a1d299375740f95f30027b8b3f4b34e7548 Mon Sep 17 00:00:00 2001 -From: Akira Shimahara <akira215corp@gmail.com> -Date: Mon, 11 May 2020 22:38:20 +0200 -Subject: [PATCH] w1_therm: adding bulk read support to trigger - multiple conversion on bus - -commit 57c76221d5af648c8355a55c09b050c5d8d38189 upstream. - -Adding bulk read support: -Sending a 'trigger' command in the dedicated sysfs entry of bus master -device send a conversion command for all the slaves on the bus. The sysfs -entry is added as soon as at least one device supporting this feature -is detected on the bus. - -The behavior of the sysfs reading temperature on the device is as follow: - * If no bulk read pending, trigger a conversion on the device, wait for - the conversion to be done, read the temperature in device RAM - * If a bulk read has been trigger, access directly the device RAM -This behavior is the same on the 2 sysfs entries ('temperature' and -'w1_slave'). - -Reading the therm_bulk_read sysfs give the status of bulk operations: - * '-1': conversion in progress on at least 1 sensor - * '1': conversion complete but at least one sensor has not been read yet - * '0': no bulk operation. Reading temperature on ecah device will trigger -a conversion - -As not all devices support bulk read feature, it has been added in device -family structure. - -The attribute is set at master level as soon as a supporting device is -discover. It is removed when the last supported device leave the bus. -The count of supported device is kept with the static counter -bulk_read_device_counter. - -A strong pull up is apply on the line if at least one device required it. -The duration of the pull up is the max time required by a device on the -line, which depends on the resolution settings of each device. The strong -pull up could be adjust with the a module parameter. - -Updating documentation in Documentation/ABI/testing/sysfs-driver-w1_therm -and Documentation/w1/slaves/w1_therm.rst accordingly. - -Signed-off-by: Akira Shimahara <akira215corp@gmail.com> -Link: https://lore.kernel.org/r/20200511203820.411483-1-akira215corp@gmail.com -Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> ---- - .../ABI/testing/sysfs-driver-w1_therm | 36 ++- - Documentation/w1/slaves/w1_therm.rst | 50 +++- - drivers/w1/slaves/w1_therm.c | 251 +++++++++++++++++- - 3 files changed, 322 insertions(+), 15 deletions(-) - ---- a/Documentation/ABI/testing/sysfs-driver-w1_therm -+++ b/Documentation/ABI/testing/sysfs-driver-w1_therm -@@ -62,9 +62,16 @@ Date: May 2020 - Contact: Akira Shimahara <akira215corp@gmail.com> - Description: - (RO) return the temperature in 1/1000 degC. -- Note that the conversion duration depend on the resolution (if -- device support this feature). It takes 94ms in 9bits -- resolution, 750ms for 12bits. -+ * If a bulk read has been triggered, it will directly -+ return the temperature computed when the bulk read -+ occurred, if available. If not yet available, nothing -+ is returned (a debug kernel message is sent), you -+ should retry later on. -+ * If no bulk read has been triggered, it will trigger -+ a conversion and send the result. Note that the -+ conversion duration depend on the resolution (if -+ device support this feature). It takes 94ms in 9bits -+ resolution, 750ms for 12bits. - Users: any user space application which wants to communicate with - w1_term device - -@@ -85,4 +92,25 @@ Description: - refer to Documentation/w1/slaves/w1_therm.rst for detailed - information. - Users: any user space application which wants to communicate with -- w1_term device -\ No newline at end of file -+ w1_term device -+ -+ -+What: /sys/bus/w1/devices/w1_bus_masterXX/therm_bulk_read -+Date: May 2020 -+Contact: Akira Shimahara <akira215corp@gmail.com> -+Description: -+ (RW) trigger a bulk read conversion. read the status -+ *read*: -+ * '-1': conversion in progress on at least 1 sensor -+ * '1' : conversion complete but at least one sensor -+ value has not been read yet -+ * '0' : no bulk operation. Reading temperature will -+ trigger a conversion on each device -+ *write*: 'trigger': trigger a bulk read on all supporting -+ devices on the bus -+ Note that if a bulk read is sent but one sensor is not read -+ immediately, the next access to temperature on this device -+ will return the temperature measured at the time of issue -+ of the bulk read command (not the current temperature). -+Users: any user space application which wants to communicate with -+ w1_term device ---- a/Documentation/w1/slaves/w1_therm.rst -+++ b/Documentation/w1/slaves/w1_therm.rst -@@ -26,20 +26,31 @@ W1_THERM_DS1825 0x3B - W1_THERM_DS28EA00 0x42 - ==================== ==== - --Support is provided through the sysfs w1_slave file. Each open and -+Support is provided through the sysfs w1_slave file. Each open and - read sequence will initiate a temperature conversion then provide two --lines of ASCII output. The first line contains the nine hex bytes -+lines of ASCII output. The first line contains the nine hex bytes - read along with a calculated crc value and YES or NO if it matched. --If the crc matched the returned values are retained. The second line -+If the crc matched the returned values are retained. The second line - displays the retained values along with a temperature in millidegrees - Centigrade after t=. - --Parasite powered devices are limited to one slave performing a --temperature conversion at a time. If none of the devices are parasite --powered it would be possible to convert all the devices at the same --time and then go back to read individual sensors. That isn't --currently supported. The driver also doesn't support reduced --precision (which would also reduce the conversion time) when reading values. -+Alternatively, temperature can be read using temperature sysfs, it -+return only temperature in millidegrees Centigrade. -+ -+A bulk read of all devices on the bus could be done writing 'trigger' -+in the therm_bulk_read sysfs entry at w1_bus_master level. This will -+sent the convert command on all devices on the bus, and if parasite -+powered devices are detected on the bus (and strong pullup is enable -+in the module), it will drive the line high during the longer conversion -+time required by parasited powered device on the line. Reading -+therm_bulk_read will return 0 if no bulk conversion pending, -+-1 if at least one sensor still in conversion, 1 if conversion is complete -+but at least one sensor value has not been read yet. Result temperature is -+then accessed by reading the temperature sysfs entry of each device, which -+may return empty if conversion is still in progress. Note that if a bulk -+read is sent but one sensor is not read immediately, the next access to -+temperature on this device will return the temperature measured at the -+time of issue of the bulk read command (not the current temperature). - - Writing a value between 9 and 12 to the sysfs w1_slave file will change the - precision of the sensor for the next readings. This value is in (volatile) -@@ -49,6 +60,27 @@ To store the current precision configura - has to be written to the sysfs w1_slave file. Since the EEPROM has a limited - amount of writes (>50k), this command should be used wisely. - -+Alternatively, resolution can be set or read (value from 9 to 12) using the -+dedicated resolution sysfs entry on each device. This sysfs entry is not -+present for devices not supporting this feature. Driver will adjust the -+correct conversion time for each device regarding to its resolution setting. -+In particular, strong pullup will be applied if required during the conversion -+duration. -+ -+The write-only sysfs entry eeprom is an alternative for EEPROM operations: -+ * 'save': will save device RAM to EEPROM -+ * 'restore': will restore EEPROM data in device RAM. -+ -+ext_power syfs entry allow tho check the power status of each device. -+ * '0': device parasite powered -+ * '1': device externally powered -+ -+sysfs alarms allow read or write TH and TL (Temperature High an Low) alarms. -+Values shall be space separated and in the device range (typical -55 degC -+to 125 degC). Values are integer as they are store in a 8bit register in -+the device. Lowest value is automatically put to TL.Once set, alarms could -+be search at master level. -+ - The module parameter strong_pullup can be set to 0 to disable the - strong pullup, 1 to enable autodetection or 2 to force strong pullup. - In case of autodetection, the driver will use the "READ POWER SUPPLY" ---- a/drivers/w1/slaves/w1_therm.c -+++ b/drivers/w1/slaves/w1_therm.c -@@ -43,6 +43,9 @@ - static int w1_strong_pullup = 1; - module_param_named(strong_pullup, w1_strong_pullup, int, 0); - -+/* Counter for devices supporting bulk reading */ -+static u16 bulk_read_device_counter; /* =0 as per C standard */ -+ - /* This command should be in public header w1.h but is not */ - #define W1_RECALL_EEPROM 0xB8 - -@@ -57,6 +60,7 @@ module_param_named(strong_pullup, w1_str - - #define EEPROM_CMD_WRITE "save" /* cmd for write eeprom sysfs */ - #define EEPROM_CMD_READ "restore" /* cmd for read eeprom sysfs */ -+#define BULK_TRIGGER_CMD "trigger" /* cmd to trigger a bulk read */ - - #define MIN_TEMP -55 /* min temperature that can be mesured */ - #define MAX_TEMP 125 /* max temperature that can be mesured */ -@@ -84,6 +88,15 @@ module_param_named(strong_pullup, w1_str - #define SLAVE_RESOLUTION(sl) \ - (((struct w1_therm_family_data *)(sl->family_data))->resolution) - -+/* -+ * return whether or not a converT command has been issued to the slave -+ * * 0: no bulk read is pending -+ * * -1: conversion is in progress -+ * * 1: conversion done, result to be read -+ */ -+#define SLAVE_CONVERT_TRIGGERED(sl) \ -+ (((struct w1_therm_family_data *)(sl->family_data))->convert_triggered) -+ - /* return the address of the refcnt in the family data */ - #define THERM_REFCNT(family_data) \ - (&((struct w1_therm_family_data *)family_data)->refcnt) -@@ -100,6 +113,7 @@ module_param_named(strong_pullup, w1_str - * @set_resolution: pointer to the device set_resolution function - * @get_resolution: pointer to the device get_resolution function - * @write_data: pointer to the device writing function (2 or 3 bytes) -+ * @bulk_read: true if device family support bulk read, false otherwise - */ - struct w1_therm_family_converter { - u8 broken; -@@ -110,6 +124,7 @@ struct w1_therm_family_converter { - int (*set_resolution)(struct w1_slave *sl, int val); - int (*get_resolution)(struct w1_slave *sl); - int (*write_data)(struct w1_slave *sl, const u8 *data); -+ bool bulk_read; - }; - - /** -@@ -120,6 +135,7 @@ struct w1_therm_family_converter { - * 0 device parasite powered, - * -x error or undefined - * @resolution: current device resolution -+ * @convert_triggered: conversion state of the device - * @specific_functions: pointer to struct of device specific function - */ - struct w1_therm_family_data { -@@ -127,6 +143,7 @@ struct w1_therm_family_data { - atomic_t refcnt; - int external_powered; - int resolution; -+ int convert_triggered; - struct w1_therm_family_converter *specific_functions; - }; - -@@ -218,6 +235,18 @@ static int recall_eeprom(struct w1_slave - */ - static int read_powermode(struct w1_slave *sl); - -+/** -+ * trigger_bulk_read() - function to trigger a bulk read on the bus -+ * @dev_master: the device master of the bus -+ * -+ * Send a SKIP ROM follow by a CONVERT T commmand on the bus. -+ * It also set the status flag in each slave &struct w1_therm_family_data -+ * to signal that a conversion is in progress. -+ * -+ * Return: 0 if success, -kernel error code otherwise -+ */ -+static int trigger_bulk_read(struct w1_master *dev_master); -+ - /* Sysfs interface declaration */ - - static ssize_t w1_slave_show(struct device *device, -@@ -250,6 +279,12 @@ static ssize_t alarms_store(struct devic - static ssize_t alarms_show(struct device *device, - struct device_attribute *attr, char *buf); - -+static ssize_t therm_bulk_read_store(struct device *device, -+ struct device_attribute *attr, const char *buf, size_t size); -+ -+static ssize_t therm_bulk_read_show(struct device *device, -+ struct device_attribute *attr, char *buf); -+ - /* Attributes declarations */ - - static DEVICE_ATTR_RW(w1_slave); -@@ -260,6 +295,8 @@ static DEVICE_ATTR_RW(resolution); - static DEVICE_ATTR_WO(eeprom); - static DEVICE_ATTR_RW(alarms); - -+static DEVICE_ATTR_RW(therm_bulk_read); /* attribut at master level */ -+ - /* Interface Functions declaration */ - - /** -@@ -572,6 +609,7 @@ static struct w1_therm_family_converter - .set_resolution = NULL, /* no config register */ - .get_resolution = NULL, /* no config register */ - .write_data = w1_DS18S20_write_data, -+ .bulk_read = true - }, - { - .f = &w1_therm_family_DS1822, -@@ -580,6 +618,7 @@ static struct w1_therm_family_converter - .set_resolution = w1_DS18B20_set_resolution, - .get_resolution = w1_DS18B20_get_resolution, - .write_data = w1_DS18B20_write_data, -+ .bulk_read = true - }, - { - .f = &w1_therm_family_DS18B20, -@@ -588,6 +627,7 @@ static struct w1_therm_family_converter - .set_resolution = w1_DS18B20_set_resolution, - .get_resolution = w1_DS18B20_get_resolution, - .write_data = w1_DS18B20_write_data, -+ .bulk_read = true - }, - { - .f = &w1_therm_family_DS28EA00, -@@ -596,6 +636,7 @@ static struct w1_therm_family_converter - .set_resolution = w1_DS18B20_set_resolution, - .get_resolution = w1_DS18B20_get_resolution, - .write_data = w1_DS18B20_write_data, -+ .bulk_read = false - }, - { - .f = &w1_therm_family_DS1825, -@@ -604,6 +645,7 @@ static struct w1_therm_family_converter - .set_resolution = w1_DS18B20_set_resolution, - .get_resolution = w1_DS18B20_get_resolution, - .write_data = w1_DS18B20_write_data, -+ .bulk_read = true - } - }; - -@@ -658,6 +700,23 @@ static inline bool bus_mutex_lock(struct - } - - /** -+ * support_bulk_read() - check if slave support bulk read -+ * @sl: device to check the ability -+ * -+ * Return: true if bulk read is supported, false if not or error -+ */ -+static inline bool bulk_read_support(struct w1_slave *sl) -+{ -+ if (SLAVE_SPECIFIC_FUNC(sl)) -+ return SLAVE_SPECIFIC_FUNC(sl)->bulk_read; -+ -+ dev_info(&sl->dev, -+ "%s: Device not supported by the driver\n", __func__); -+ -+ return false; /* No device family */ -+} -+ -+/** - * conversion_time() - get the Tconv for the slave - * @sl: device to get the conversion time - * -@@ -741,6 +800,24 @@ static int w1_therm_add_slave(struct w1_ - /* save this pointer to the device structure */ - SLAVE_SPECIFIC_FUNC(sl) = sl_family_conv; - -+ if (bulk_read_support(sl)) { -+ /* -+ * add the sys entry to trigger bulk_read -+ * at master level only the 1st time -+ */ -+ if (!bulk_read_device_counter) { -+ int err = device_create_file(&sl->master->dev, -+ &dev_attr_therm_bulk_read); -+ -+ if (err) -+ dev_warn(&sl->dev, -+ "%s: Device has been added, but bulk read is unavailable. err=%d\n", -+ __func__, err); -+ } -+ /* Increment the counter */ -+ bulk_read_device_counter++; -+ } -+ - /* Getting the power mode of the device {external, parasite} */ - SLAVE_POWERMODE(sl) = read_powermode(sl); - -@@ -763,6 +840,9 @@ static int w1_therm_add_slave(struct w1_ - } - } - -+ /* Finally initialize convert_triggered flag */ -+ SLAVE_CONVERT_TRIGGERED(sl) = 0; -+ - return 0; - } - -@@ -770,6 +850,14 @@ static void w1_therm_remove_slave(struct - { - int refcnt = atomic_sub_return(1, THERM_REFCNT(sl->family_data)); - -+ if (bulk_read_support(sl)) { -+ bulk_read_device_counter--; -+ /* Delete the entry if no more device support the feature */ -+ if (!bulk_read_device_counter) -+ device_remove_file(&sl->master->dev, -+ &dev_attr_therm_bulk_read); -+ } -+ - while (refcnt) { - msleep(1000); - refcnt = atomic_read(THERM_REFCNT(sl->family_data)); -@@ -1084,6 +1172,96 @@ error: - return ret; - } - -+static int trigger_bulk_read(struct w1_master *dev_master) -+{ -+ struct w1_slave *sl = NULL; /* used to iterate through slaves */ -+ int max_trying = W1_THERM_MAX_TRY; -+ int t_conv = 0; -+ int ret = -ENODEV; -+ bool strong_pullup = false; -+ -+ /* -+ * Check whether there are parasite powered device on the bus, -+ * and compute duration of conversion for these devices -+ * so we can apply a strong pullup if required -+ */ -+ list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { -+ if (!sl->family_data) -+ goto error; -+ if (bulk_read_support(sl)) { -+ int t_cur = conversion_time(sl); -+ -+ t_conv = t_cur > t_conv ? t_cur : t_conv; -+ strong_pullup = strong_pullup || -+ (w1_strong_pullup == 2 || -+ (!SLAVE_POWERMODE(sl) && -+ w1_strong_pullup)); -+ } -+ } -+ -+ /* -+ * t_conv is the max conversion time required on the bus -+ * If its 0, no device support the bulk read feature -+ */ -+ if (!t_conv) -+ goto error; -+ -+ if (!bus_mutex_lock(&dev_master->bus_mutex)) { -+ ret = -EAGAIN; /* Didn't acquire the mutex */ -+ goto error; -+ } -+ -+ while ((max_trying--) && (ret < 0)) { /* ret should be either 0 */ -+ -+ if (!w1_reset_bus(dev_master)) { /* Just reset the bus */ -+ unsigned long sleep_rem; -+ -+ w1_write_8(dev_master, W1_SKIP_ROM); -+ -+ if (strong_pullup) /* Apply pullup if required */ -+ w1_next_pullup(dev_master, t_conv); -+ -+ w1_write_8(dev_master, W1_CONVERT_TEMP); -+ -+ /* set a flag to instruct that converT pending */ -+ list_for_each_entry(sl, -+ &dev_master->slist, w1_slave_entry) { -+ if (bulk_read_support(sl)) -+ SLAVE_CONVERT_TRIGGERED(sl) = -1; -+ } -+ -+ if (strong_pullup) { /* some device need pullup */ -+ sleep_rem = msleep_interruptible(t_conv); -+ if (sleep_rem != 0) { -+ ret = -EINTR; -+ goto mt_unlock; -+ } -+ mutex_unlock(&dev_master->bus_mutex); -+ } else { -+ mutex_unlock(&dev_master->bus_mutex); -+ sleep_rem = msleep_interruptible(t_conv); -+ if (sleep_rem != 0) { -+ ret = -EINTR; -+ goto set_flag; -+ } -+ } -+ ret = 0; -+ goto set_flag; -+ } -+ } -+ -+mt_unlock: -+ mutex_unlock(&dev_master->bus_mutex); -+set_flag: -+ /* set a flag to register convsersion is done */ -+ list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { -+ if (bulk_read_support(sl)) -+ SLAVE_CONVERT_TRIGGERED(sl) = 1; -+ } -+error: -+ return ret; -+} -+ - /* Sysfs Interface definition */ - - static ssize_t w1_slave_show(struct device *device, -@@ -1095,7 +1273,20 @@ static ssize_t w1_slave_show(struct devi - int ret, i; - ssize_t c = PAGE_SIZE; - -- ret = convert_t(sl, &info); -+ if (bulk_read_support(sl)) { -+ if (SLAVE_CONVERT_TRIGGERED(sl) < 0) { -+ dev_dbg(device, -+ "%s: Conversion in progress, retry later\n", -+ __func__); -+ return 0; -+ } else if (SLAVE_CONVERT_TRIGGERED(sl) > 0) { -+ /* A bulk read has been issued, read the device RAM */ -+ ret = read_scratchpad(sl, &info); -+ SLAVE_CONVERT_TRIGGERED(sl) = 0; -+ } else -+ ret = convert_t(sl, &info); -+ } else -+ ret = convert_t(sl, &info); - - if (ret < 0) { - dev_dbg(device, -@@ -1176,7 +1367,20 @@ static ssize_t temperature_show(struct d - return 0; /* No device family */ - } - -- ret = convert_t(sl, &info); -+ if (bulk_read_support(sl)) { -+ if (SLAVE_CONVERT_TRIGGERED(sl) < 0) { -+ dev_dbg(device, -+ "%s: Conversion in progress, retry later\n", -+ __func__); -+ return 0; -+ } else if (SLAVE_CONVERT_TRIGGERED(sl) > 0) { -+ /* A bulk read has been issued, read the device RAM */ -+ ret = read_scratchpad(sl, &info); -+ SLAVE_CONVERT_TRIGGERED(sl) = 0; -+ } else -+ ret = convert_t(sl, &info); -+ } else -+ ret = convert_t(sl, &info); - - if (ret < 0) { - dev_dbg(device, -@@ -1412,6 +1616,49 @@ free_m: - return size; - } - -+static ssize_t therm_bulk_read_store(struct device *device, -+ struct device_attribute *attr, const char *buf, size_t size) -+{ -+ struct w1_master *dev_master = dev_to_w1_master(device); -+ int ret = -EINVAL; /* Invalid argument */ -+ -+ if (size == sizeof(BULK_TRIGGER_CMD)) -+ if (!strncmp(buf, BULK_TRIGGER_CMD, -+ sizeof(BULK_TRIGGER_CMD)-1)) -+ ret = trigger_bulk_read(dev_master); -+ -+ if (ret) -+ dev_info(device, -+ "%s: unable to trigger a bulk read on the bus. err=%d\n", -+ __func__, ret); -+ -+ return size; -+} -+ -+static ssize_t therm_bulk_read_show(struct device *device, -+ struct device_attribute *attr, char *buf) -+{ -+ struct w1_master *dev_master = dev_to_w1_master(device); -+ struct w1_slave *sl = NULL; -+ int ret = 0; -+ -+ list_for_each_entry(sl, &dev_master->slist, w1_slave_entry) { -+ if (sl->family_data) { -+ if (bulk_read_support(sl)) { -+ if (SLAVE_CONVERT_TRIGGERED(sl) == -1) { -+ ret = -1; -+ goto show_result; -+ } -+ if (SLAVE_CONVERT_TRIGGERED(sl) == 1) -+ /* continue to check other slaves */ -+ ret = 1; -+ } -+ } -+ } -+show_result: -+ return sprintf(buf, "%d\n", ret); -+} -+ - #if IS_REACHABLE(CONFIG_HWMON) - static int w1_read_temp(struct device *device, u32 attr, int channel, - long *val) |