diff options
Diffstat (limited to 'drivers/hwmon/applesmc.c')
| -rw-r--r-- | drivers/hwmon/applesmc.c | 193 |
1 files changed, 119 insertions, 74 deletions
diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c index ec93b8d673f5..fc6d6a9053ce 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 @@ -151,59 +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) { u8 status; int us; - for (us = APPLESMC_MIN_WAIT; us < APPLESMC_MAX_WAIT; us <<= 1) { - udelay(us); + int i; + + 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; + 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; + 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) { - udelay(us); - 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 (us << 1 == APPLESMC_MAX_WAIT) - 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) @@ -220,6 +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); @@ -233,7 +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; } @@ -244,19 +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); @@ -275,7 +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) @@ -351,7 +391,7 @@ static const struct applesmc_entry *applesmc_get_entry_by_index(int index) cache->len = info[0]; memcpy(cache->type, &info[1], 4); cache->flags = info[5]; - cache->valid = 1; + cache->valid = true; out: mutex_unlock(&smcreg.mutex); @@ -525,7 +565,7 @@ static int applesmc_init_index(struct applesmc_registers *s) static int applesmc_init_smcreg_try(void) { struct applesmc_registers *s = &smcreg; - bool left_light_sensor = 0, right_light_sensor = 0; + bool left_light_sensor = false, right_light_sensor = false; unsigned int count; u8 tmp[1]; int ret; @@ -701,7 +741,7 @@ static void applesmc_idev_poll(struct input_dev *idev) static ssize_t applesmc_name_show(struct device *dev, struct device_attribute *attr, char *buf) { - return snprintf(buf, PAGE_SIZE, "applesmc\n"); + return sysfs_emit(buf, "applesmc\n"); } static ssize_t applesmc_position_show(struct device *dev, @@ -723,8 +763,8 @@ static ssize_t applesmc_position_show(struct device *dev, out: if (ret) return ret; - else - return snprintf(buf, PAGE_SIZE, "(%d,%d,%d)\n", x, y, z); + + return sysfs_emit(buf, "(%d,%d,%d)\n", x, y, z); } static ssize_t applesmc_light_show(struct device *dev, @@ -747,22 +787,25 @@ static ssize_t applesmc_light_show(struct device *dev, } ret = applesmc_read_key(LIGHT_SENSOR_LEFT_KEY, buffer, data_length); + if (ret) + goto out; /* newer macbooks report a single 10-bit bigendian value */ if (data_length == 10) { left = be16_to_cpu(*(__be16 *)(buffer + 6)) >> 2; goto out; } left = buffer[2]; + + ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length); if (ret) goto out; - ret = applesmc_read_key(LIGHT_SENSOR_RIGHT_KEY, buffer, data_length); right = buffer[2]; out: if (ret) return ret; - else - return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", left, right); + + return sysfs_emit(sysfsbuf, "(%d,%d)\n", left, right); } /* Displays sensor key as label */ @@ -771,7 +814,7 @@ static ssize_t applesmc_show_sensor_label(struct device *dev, { const char *key = smcreg.index[to_index(devattr)]; - return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", key); + return sysfs_emit(sysfsbuf, "%s\n", key); } /* Displays degree Celsius * 1000 */ @@ -789,7 +832,7 @@ static ssize_t applesmc_show_temperature(struct device *dev, temp = 250 * (value >> 6); - return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", temp); + return sysfs_emit(sysfsbuf, "%d\n", temp); } static ssize_t applesmc_show_fan_speed(struct device *dev, @@ -804,12 +847,11 @@ static ssize_t applesmc_show_fan_speed(struct device *dev, to_index(attr)); ret = applesmc_read_key(newkey, buffer, 2); - speed = ((buffer[0] << 8 | buffer[1]) >> 2); - if (ret) return ret; - else - return snprintf(sysfsbuf, PAGE_SIZE, "%u\n", speed); + + speed = ((buffer[0] << 8 | buffer[1]) >> 2); + return sysfs_emit(sysfsbuf, "%u\n", speed); } static ssize_t applesmc_store_fan_speed(struct device *dev, @@ -845,12 +887,11 @@ static ssize_t applesmc_show_fan_manual(struct device *dev, u8 buffer[2]; ret = applesmc_read_key(FANS_MANUAL, buffer, 2); - manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01; - if (ret) return ret; - else - return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", manual); + + manual = ((buffer[0] << 8 | buffer[1]) >> to_index(attr)) & 0x01; + return sysfs_emit(sysfsbuf, "%d\n", manual); } static ssize_t applesmc_store_fan_manual(struct device *dev, @@ -866,10 +907,11 @@ static ssize_t applesmc_store_fan_manual(struct device *dev, return -EINVAL; ret = applesmc_read_key(FANS_MANUAL, buffer, 2); - val = (buffer[0] << 8 | buffer[1]); if (ret) goto out; + val = (buffer[0] << 8 | buffer[1]); + if (input) val = val | (0x01 << to_index(attr)); else @@ -901,14 +943,14 @@ static ssize_t applesmc_show_fan_position(struct device *dev, if (ret) return ret; - else - return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", buffer+4); + + return sysfs_emit(sysfsbuf, "%s\n", buffer + 4); } static ssize_t applesmc_calibrate_show(struct device *dev, struct device_attribute *attr, char *sysfsbuf) { - return snprintf(sysfsbuf, PAGE_SIZE, "(%d,%d)\n", rest_x, rest_y); + return sysfs_emit(sysfsbuf, "(%d,%d)\n", rest_x, rest_y); } static ssize_t applesmc_calibrate_store(struct device *dev, @@ -945,13 +987,12 @@ static ssize_t applesmc_key_count_show(struct device *dev, u32 count; ret = applesmc_read_key(KEY_COUNT_KEY, buffer, 4); - count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) + - ((u32)buffer[2]<<8) + buffer[3]; - if (ret) return ret; - else - return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", count); + + count = ((u32)buffer[0]<<24) + ((u32)buffer[1]<<16) + + ((u32)buffer[2]<<8) + buffer[3]; + return sysfs_emit(sysfsbuf, "%d\n", count); } static ssize_t applesmc_key_at_index_read_show(struct device *dev, @@ -979,7 +1020,7 @@ static ssize_t applesmc_key_at_index_data_length_show(struct device *dev, if (IS_ERR(entry)) return PTR_ERR(entry); - return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry->len); + return sysfs_emit(sysfsbuf, "%d\n", entry->len); } static ssize_t applesmc_key_at_index_type_show(struct device *dev, @@ -991,7 +1032,7 @@ static ssize_t applesmc_key_at_index_type_show(struct device *dev, if (IS_ERR(entry)) return PTR_ERR(entry); - return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->type); + return sysfs_emit(sysfsbuf, "%s\n", entry->type); } static ssize_t applesmc_key_at_index_name_show(struct device *dev, @@ -1003,13 +1044,13 @@ static ssize_t applesmc_key_at_index_name_show(struct device *dev, if (IS_ERR(entry)) return PTR_ERR(entry); - return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key); + return sysfs_emit(sysfsbuf, "%s\n", entry->key); } static ssize_t applesmc_key_at_index_show(struct device *dev, struct device_attribute *attr, char *sysfsbuf) { - return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", key_at_index); + return sysfs_emit(sysfsbuf, "%d\n", key_at_index); } static ssize_t applesmc_key_at_index_store(struct device *dev, @@ -1258,6 +1299,10 @@ static const struct dmi_system_id applesmc_whitelist[] __initconst = { DMI_MATCH(DMI_BOARD_VENDOR, "Apple"), DMI_MATCH(DMI_PRODUCT_NAME, "iMac") }, }, + { applesmc_dmi_match, "Apple Xserve", { + DMI_MATCH(DMI_BOARD_VENDOR, "Apple"), + DMI_MATCH(DMI_PRODUCT_NAME, "Xserve") }, + }, { .ident = NULL } }; |