Version two of refactored driver

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

1 files changed, 119 insertions, 133 deletions

diff --git a/usr/src/dkms_source_tree/applesmc.c b/usr/src/dkms_source_tree/applesmc.c
index 2eb78e3..01071e5 100644
--- a/usr/src/dkms_source_tree/applesmc.c
+++ b/usr/src/dkms_source_tree/applesmc.c
@@ -91,7 +91,7 @@
 #define FAN_ID_FMT              "F%dID" /* r-o char[16] */
 
 /* List of keys used to read/write fan speeds */
-static const char *fan_speed_fmt[] = {
+static const char *const fan_speed_fmt[] = {
         "F%dAc",                /* actual speed */
         "F%dMn",                /* minimum speed (rw) */
         "F%dMx",                /* maximum speed */
@@ -133,7 +133,8 @@ struct applesmc_entry {
         char key[5];            /* four-letter key code */
         u8 valid;               /* set when entry is successfully read once */
         u8 len;                 /* bounded by APPLESMC_MAX_DATA_LENGTH */
-        char type[5];           /* four-letter type code (padded) */
+        char type[5];           /* four-letter type code */
+        u8 flags;               /* 0x10: func; 0x40: write; 0x80: read */
 };
 
 /* Register lookup and registers common to all SMCs */
@@ -144,12 +145,11 @@ static struct applesmc_registers {
         unsigned int temp_count;        /* number of temperature registers */
         unsigned int temp_begin;        /* temperature lower index bound */
         unsigned int temp_end;          /* temperature upper index bound */
+        int num_light_sensors;          /* number of light sensors */
         bool has_accelerometer;         /* has motion sensor */
-        bool has_left_light;            /* has left light sensor */
-        bool has_right_light;           /* has right light sensor */
-        bool has_key_light;             /* has keyboard backlight */
+        bool has_key_backlight;         /* has keyboard backlight */
         bool init_complete;             /* true when fully initialized */
-        struct applesmc_entry *entry;   /* key entries */
+        struct applesmc_entry *cache;   /* cached key entries */
 } smcreg;
 
 static const int debug;
@@ -167,7 +167,6 @@ static struct input_polled_dev *applesmc_idev;
  */
 static unsigned int key_at_index;
 
-
 static struct workqueue_struct *applesmc_led_wq;
 
 /*
@@ -311,48 +310,52 @@ static int applesmc_write_entry(const struct applesmc_entry *entry,
         return ret;
 }
 
-static int applesmc_get_entry_by_index(int index, struct applesmc_entry *entry)
+static const struct applesmc_entry *applesmc_get_entry_by_index(int index)
 {
-        struct applesmc_entry *cache = &smcreg.entry[index];
+        struct applesmc_entry *cache = &smcreg.cache[index];
+        u8 key[4], info[6];
         __be32 be;
-        int ret;
+        int ret = 0;
 
-        if (cache->valid) {
-                memcpy(entry, cache, sizeof(*entry));
-                return 0;
-        }
+        if (cache->valid)
+                return cache;
 
         mutex_lock(&smcreg.mutex);
 
+        if (cache->valid)
+                goto out;
         be = cpu_to_be32(index);
-        ret = read_smc(APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, cache->key, 4);
+        ret = read_smc(APPLESMC_GET_KEY_BY_INDEX_CMD, (u8 *)&be, key, 4);
         if (ret)
                 goto out;
-        ret = read_smc(APPLESMC_GET_KEY_TYPE_CMD, cache->key, &cache->len, 6);
+        ret = read_smc(APPLESMC_GET_KEY_TYPE_CMD, key, info, 6);
         if (ret)
                 goto out;
 
-        cache->type[4] = 0;
+        memcpy(cache->key, key, 4);
+        cache->len = info[0];
+        memcpy(cache->type, &info[1], 4);
+        cache->flags = info[5];
         cache->valid = 1;
-        memcpy(entry, cache, sizeof(*entry));
 
 out:
         mutex_unlock(&smcreg.mutex);
-        return ret;
+        if (ret)
+                return ERR_PTR(ret);
+        return cache;
 }
 
 static int applesmc_get_lower_bound(unsigned int *lo, const char *key)
 {
         int begin = 0, end = smcreg.key_count;
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
         while (begin != end) {
                 int middle = begin + (end - begin) / 2;
-                ret = applesmc_get_entry_by_index(middle, &entry);
-                if (ret)
-                        return ret;
-                if (strcmp(entry.key, key) < 0)
+                entry = applesmc_get_entry_by_index(middle);
+                if (IS_ERR(entry))
+                        return PTR_ERR(entry);
+                if (strcmp(entry->key, key) < 0)
                         begin = middle + 1;
                 else
                         end = middle;
@@ -365,15 +368,14 @@ static int applesmc_get_lower_bound(unsigned int *lo, const char *key)
 static int applesmc_get_upper_bound(unsigned int *hi, const char *key)
 {
         int begin = 0, end = smcreg.key_count;
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
         while (begin != end) {
                 int middle = begin + (end - begin) / 2;
-                ret = applesmc_get_entry_by_index(middle, &entry);
-                if (ret)
-                        return ret;
-                if (strcmp(key, entry.key) < 0)
+                entry = applesmc_get_entry_by_index(middle);
+                if (IS_ERR(entry))
+                        return PTR_ERR(entry);
+                if (strcmp(key, entry->key) < 0)
                         end = middle;
                 else
                         begin = middle + 1;
@@ -383,58 +385,54 @@ static int applesmc_get_upper_bound(unsigned int *hi, const char *key)
         return 0;
 }
 
-static int applesmc_get_entry_by_key(const char *key,
-                                     struct applesmc_entry *entry)
+static const struct applesmc_entry *applesmc_get_entry_by_key(const char *key)
 {
         int begin, end;
         int ret;
 
         ret = applesmc_get_lower_bound(&begin, key);
         if (ret)
-                return ret;
+                return ERR_PTR(ret);
         ret = applesmc_get_upper_bound(&end, key);
         if (ret)
-                return ret;
+                return ERR_PTR(ret);
         if (end - begin != 1)
-                return -EINVAL;
+                return ERR_PTR(-EINVAL);
 
-        return applesmc_get_entry_by_index(begin, entry);
+        return applesmc_get_entry_by_index(begin);
 }
 
 static int applesmc_read_key(const char *key, u8 *buffer, u8 len)
 {
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_key(key, &entry);
-        if (ret)
-                return ret;
+        entry = applesmc_get_entry_by_key(key);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
 
-        return applesmc_read_entry(&entry, buffer, len);
+        return applesmc_read_entry(entry, buffer, len);
 }
 
 static int applesmc_write_key(const char *key, const u8 *buffer, u8 len)
 {
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_key(key, &entry);
-        if (ret)
-                return ret;
+        entry = applesmc_get_entry_by_key(key);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
 
-        return applesmc_write_entry(&entry, buffer, len);
+        return applesmc_write_entry(entry, buffer, len);
 }
 
 static int applesmc_has_key(const char *key, bool *value)
 {
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_key(key, &entry);
-        if (ret && ret != -EINVAL)
-                return ret;
+        entry = applesmc_get_entry_by_key(key);
+        if (IS_ERR(entry) && PTR_ERR(entry) != -EINVAL)
+                return PTR_ERR(entry);
 
-        *value = ret == 0 && entry.len;
+        *value = !IS_ERR(entry);
         return 0;
 }
 
@@ -466,23 +464,20 @@ static int applesmc_read_motion_sensor(int index, s16* value)
 }
 
 /*
- * applesmc_device_init - initialize the accelerometer.  Returns zero on success
- * and negative error code on failure.  Can sleep.
+ * applesmc_device_init - initialize the accelerometer.  Can sleep.
  */
-static int applesmc_device_init(void)
+static void applesmc_device_init(void)
 {
-        int total, ret = -ENXIO;
+        int total;
         u8 buffer[2];
 
         if (!smcreg.has_accelerometer)
-                return 0;
+                return;
 
         for (total = INIT_TIMEOUT_MSECS; total > 0; total -= INIT_WAIT_MSECS) {
                 if (!applesmc_read_key(MOTION_SENSOR_KEY, buffer, 2) &&
-                                (buffer[0] != 0x00 || buffer[1] != 0x00)) {
-                        ret = 0;
-                        goto out;
-                }
+                                (buffer[0] != 0x00 || buffer[1] != 0x00))
+                        return;
                 buffer[0] = 0xe0;
                 buffer[1] = 0x00;
                 applesmc_write_key(MOTION_SENSOR_KEY, buffer, 2);
@@ -490,9 +485,6 @@ static int applesmc_device_init(void)
         }
 
         pr_warn("failed to init the device\n");
-
-out:
-        return ret;
 }
 
 /*
@@ -501,7 +493,8 @@ out:
 static int applesmc_init_smcreg_try(void)
 {
         struct applesmc_registers *s = &smcreg;
-        u8 tmp[4];
+        bool left_light_sensor, right_light_sensor;
+        u8 tmp[1];
         int ret;
 
         if (s->init_complete)
@@ -513,9 +506,9 @@ static int applesmc_init_smcreg_try(void)
         if (ret)
                 return ret;
 
-        if (!s->entry)
-                s->entry = kcalloc(s->key_count, sizeof(*s->entry), GFP_KERNEL);
-        if (!s->entry)
+        if (!s->cache)
+                s->cache = kcalloc(s->key_count, sizeof(*s->cache), GFP_KERNEL);
+        if (!s->cache)
                 return -ENOMEM;
 
         ret = applesmc_read_key(FANS_COUNT, tmp, 1);
@@ -531,26 +524,27 @@ static int applesmc_init_smcreg_try(void)
                 return ret;
         s->temp_count = s->temp_end - s->temp_begin;
 
-        ret = applesmc_has_key(LIGHT_SENSOR_LEFT_KEY, &s->has_left_light);
+        ret = applesmc_has_key(LIGHT_SENSOR_LEFT_KEY, &left_light_sensor);
         if (ret)
                 return ret;
-        ret = applesmc_has_key(LIGHT_SENSOR_RIGHT_KEY, &s->has_right_light);
+        ret = applesmc_has_key(LIGHT_SENSOR_RIGHT_KEY, &right_light_sensor);
         if (ret)
                 return ret;
         ret = applesmc_has_key(MOTION_SENSOR_KEY, &s->has_accelerometer);
         if (ret)
                 return ret;
-        ret = applesmc_has_key(BACKLIGHT_KEY, &s->has_key_light);
+        ret = applesmc_has_key(BACKLIGHT_KEY, &s->has_key_backlight);
         if (ret)
                 return ret;
 
+        s->num_light_sensors = left_light_sensor + right_light_sensor;
         s->init_complete = true;
 
-        pr_info("key=%d fan=%d temp=%d acc=%d, light=%d, keyb=%d\n",
+        pr_info("key=%d fan=%d temp=%d acc=%d lux=%d kbd=%d\n",
                s->key_count, s->fan_count, s->temp_count,
                s->has_accelerometer,
-               s->has_left_light + s->has_right_light,
-               s->has_key_light);
+               s->num_light_sensors,
+               s->has_key_backlight);
 
         return 0;
 }
@@ -578,8 +572,8 @@ static int applesmc_init_smcreg(void)
 
 static void applesmc_destroy_smcreg(void)
 {
-        kfree(smcreg.entry);
-        smcreg.entry = NULL;
+        kfree(smcreg.cache);
+        memset(&smcreg, 0, sizeof(smcreg));
 }
 
 /* Device model stuff */
@@ -599,7 +593,7 @@ static int applesmc_probe(struct platform_device *dev)
 /* Synchronize device with memorized backlight state */
 static int applesmc_pm_resume(struct device *dev)
 {
-        if (smcreg.has_key_light)
+        if (smcreg.has_key_backlight)
                 applesmc_write_key(BACKLIGHT_KEY, backlight_state, 2);
         return 0;
 }
@@ -686,17 +680,19 @@ out:
 static ssize_t applesmc_light_show(struct device *dev,
                                 struct device_attribute *attr, char *sysfsbuf)
 {
-        struct applesmc_entry entry;
+        const struct applesmc_entry *entry;
         static int data_length;
         int ret;
         u8 left = 0, right = 0;
         u8 buffer[10];
 
         if (!data_length) {
-                ret = applesmc_get_entry_by_key(LIGHT_SENSOR_LEFT_KEY, &entry);
-                if (ret)
-                        goto out;
-                data_length = clamp_val(entry.len, 0, 10);
+                entry = applesmc_get_entry_by_key(LIGHT_SENSOR_LEFT_KEY);
+                if (IS_ERR(entry))
+                        return PTR_ERR(entry);
+                if (entry->len > 10)
+                        return -ENXIO;
+                data_length = entry->len;
                 pr_info("light sensor data length set to %d\n", data_length);
         }
 
@@ -724,14 +720,13 @@ static ssize_t applesmc_show_sensor_label(struct device *dev,
                         struct device_attribute *devattr, char *sysfsbuf)
 {
         int index = smcreg.temp_begin + to_index(devattr);
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_index(index, &entry);
-        if (ret)
-                return ret;
+        entry = applesmc_get_entry_by_index(index);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
 
-        return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry.key);
+        return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
 }
 
 /* Displays degree Celsius * 1000 */
@@ -739,26 +734,25 @@ static ssize_t applesmc_show_temperature(struct device *dev,
                         struct device_attribute *devattr, char *sysfsbuf)
 {
         int index = smcreg.temp_begin + to_index(devattr);
-        struct applesmc_entry entry;
+        const struct applesmc_entry *entry;
         int ret;
         u8 buffer[2];
         unsigned int temp;
 
-        ret = applesmc_get_entry_by_index(index, &entry);
-        if (ret)
-                return ret;
-        if (entry.len > 2)
+        entry = applesmc_get_entry_by_index(index);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
+        if (entry->len > 2)
                 return -EINVAL;
 
-        ret = applesmc_read_entry(&entry, buffer, entry.len);
+        ret = applesmc_read_entry(entry, buffer, entry->len);
         if (ret)
                 return ret;
 
-        if (entry.len == 2) {
-                temp = buffer[0]*1000;
+        if (entry->len == 2) {
+                temp = buffer[0] * 1000;
                 temp += (buffer[1] >> 6) * 250;
         } else {
-                /* wild guess */
                 temp = buffer[0] * 4000;
         }
 
@@ -929,56 +923,53 @@ static ssize_t applesmc_key_count_show(struct device *dev,
 static ssize_t applesmc_key_at_index_read_show(struct device *dev,
                                 struct device_attribute *attr, char *sysfsbuf)
 {
-        struct applesmc_entry entry;
+        const struct applesmc_entry *entry;
         int ret;
 
-        ret = applesmc_get_entry_by_index(key_at_index, &entry);
-        if (ret)
-                return ret;
-        ret = applesmc_read_entry(&entry, sysfsbuf, entry.len);
+        entry = applesmc_get_entry_by_index(key_at_index);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
+        ret = applesmc_read_entry(entry, sysfsbuf, entry->len);
         if (ret)
                 return ret;
 
-        return entry.len;
+        return entry->len;
 }
 
 static ssize_t applesmc_key_at_index_data_length_show(struct device *dev,
                                 struct device_attribute *attr, char *sysfsbuf)
 {
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_index(key_at_index, &entry);
-        if (ret)
-                return ret;
+        entry = applesmc_get_entry_by_index(key_at_index);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
 
-        return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry.len);
+        return snprintf(sysfsbuf, PAGE_SIZE, "%d\n", entry->len);
 }
 
 static ssize_t applesmc_key_at_index_type_show(struct device *dev,
                                 struct device_attribute *attr, char *sysfsbuf)
 {
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_index(key_at_index, &entry);
-        if (ret)
-                return ret;
+        entry = applesmc_get_entry_by_index(key_at_index);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
 
-        return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry.type);
+        return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->type);
 }
 
 static ssize_t applesmc_key_at_index_name_show(struct device *dev,
                                 struct device_attribute *attr, char *sysfsbuf)
 {
-        struct applesmc_entry entry;
-        int ret;
+        const struct applesmc_entry *entry;
 
-        ret = applesmc_get_entry_by_index(key_at_index, &entry);
-        if (ret)
-                return ret;
+        entry = applesmc_get_entry_by_index(key_at_index);
+        if (IS_ERR(entry))
+                return PTR_ERR(entry);
 
-        return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry.key);
+        return snprintf(sysfsbuf, PAGE_SIZE, "%s\n", entry->key);
 }
 
 static ssize_t applesmc_key_at_index_show(struct device *dev,
@@ -1163,21 +1154,21 @@ static void applesmc_release_accelerometer(void)
 
 static int applesmc_create_light_sensor(void)
 {
-        if (!smcreg.has_left_light)
+        if (!smcreg.num_light_sensors)
                 return 0;
         return applesmc_create_nodes(light_sensor_group, 1);
 }
 
 static void applesmc_release_light_sensor(void)
 {
-        if (!smcreg.has_left_light)
+        if (!smcreg.num_light_sensors)
                 return;
         applesmc_destroy_nodes(light_sensor_group);
 }
 
 static int applesmc_create_key_backlight(void)
 {
-        if (!smcreg.has_key_light)
+        if (!smcreg.has_key_backlight)
                 return 0;
         applesmc_led_wq = create_singlethread_workqueue("applesmc-led");
         if (!applesmc_led_wq)
@@ -1187,7 +1178,7 @@ static int applesmc_create_key_backlight(void)
 
 static void applesmc_release_key_backlight(void)
 {
-        if (!smcreg.has_key_light)
+        if (!smcreg.has_key_backlight)
                 return;
         led_classdev_unregister(&applesmc_backlight);
         destroy_workqueue(applesmc_led_wq);
@@ -1195,7 +1186,6 @@ static void applesmc_release_key_backlight(void)
 
 static int applesmc_dmi_match(const struct dmi_system_id *id)
 {
-        pr_info("%s detected\n", id->ident);
         return 1;
 }
 
@@ -1291,8 +1281,6 @@ static int __init applesmc_init(void)
                 goto out_light_ledclass;
         }
 
-        pr_info("driver successfully loaded\n");
-
         return 0;
 
 out_light_ledclass:
@@ -1333,8 +1321,6 @@ static void __exit applesmc_exit(void)
         platform_device_unregister(pdev);
         platform_driver_unregister(&applesmc_driver);
         release_region(APPLESMC_DATA_PORT, APPLESMC_NR_PORTS);
-
-        pr_info("driver unloaded\n");
 }
 
 module_init(applesmc_init);