ACPI: thinkpad-acpi: prepare light and LED for sysfs support

Do some preparatory work to add sysfs support to the thinklight and
thinkpad leds driver.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 136 insertions, 55 deletions

diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 2b73dfafac9d..5a3fb09f10d3 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -67,6 +67,7 @@
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/input.h>
+#include <linux/leds.h>
 #include <asm/uaccess.h>
 
 #include <linux/dmi.h>
@@ -85,6 +86,8 @@
 #define TP_CMOS_VOLUME_MUTE     2
 #define TP_CMOS_BRIGHTNESS_UP   4
 #define TP_CMOS_BRIGHTNESS_DOWN 5
+#define TP_CMOS_THINKLIGHT_ON   12
+#define TP_CMOS_THINKLIGHT_OFF  13
 
 /* NVRAM Addresses */
 enum tp_nvram_addr {
@@ -269,6 +272,13 @@ static enum {
 static int experimental;
 static u32 dbg_level;
 
+/* Special LED class that can defer work */
+struct tpacpi_led_classdev {
+        struct led_classdev led_classdev;
+        struct work_struct work;
+        enum led_brightness new_brightness;
+};
+
 /****************************************************************************
  ****************************************************************************
  *
@@ -3237,6 +3247,39 @@ static struct ibm_struct video_driver_data = {
 TPACPI_HANDLE(lght, root, "\\LGHT");    /* A21e, A2xm/p, T20-22, X20-21 */
 TPACPI_HANDLE(ledb, ec, "LEDB");                /* G4x */
 
+static int light_get_status(void)
+{
+        int status = 0;
+
+        if (tp_features.light_status) {
+                if (!acpi_evalf(ec_handle, &status, "KBLT", "d"))
+                        return -EIO;
+                return (!!status);
+        }
+
+        return -ENXIO;
+}
+
+static int light_set_status(int status)
+{
+        int rc;
+
+        if (tp_features.light) {
+                if (cmos_handle) {
+                        rc = acpi_evalf(cmos_handle, NULL, NULL, "vd",
+                                        (status)?
+                                                TP_CMOS_THINKLIGHT_ON :
+                                                TP_CMOS_THINKLIGHT_OFF);
+                } else {
+                        rc = acpi_evalf(lght_handle, NULL, NULL, "vd",
+                                        (status)? 1 : 0);
+                }
+                return (rc)? 0 : -EIO;
+        }
+
+        return -ENXIO;
+}
+
 static int __init light_init(struct ibm_init_struct *iibm)
 {
         vdbg_printk(TPACPI_DBG_INIT, "initializing light subdriver\n");
@@ -3263,7 +3306,7 @@ static int __init light_init(struct ibm_init_struct *iibm)
 static int light_read(char *p)
 {
         int len = 0;
-        int status = 0;
+        int status;
 
         if (!tp_features.light) {
                 len += sprintf(p + len, "status:\t\tnot supported\n");
@@ -3271,8 +3314,9 @@ static int light_read(char *p)
                 len += sprintf(p + len, "status:\t\tunknown\n");
                 len += sprintf(p + len, "commands:\ton, off\n");
         } else {
-                if (!acpi_evalf(ec_handle, &status, "KBLT", "d"))
-                        return -EIO;
+                status = light_get_status();
+                if (status < 0)
+                        return status;
                 len += sprintf(p + len, "status:\t\t%s\n", onoff(status, 0));
                 len += sprintf(p + len, "commands:\ton, off\n");
         }
@@ -3282,31 +3326,22 @@ static int light_read(char *p)
 
 static int light_write(char *buf)
 {
-        int cmos_cmd, lght_cmd;
         char *cmd;
-        int success;
+        int newstatus = 0;
 
         if (!tp_features.light)
                 return -ENODEV;
 
         while ((cmd = next_cmd(&buf))) {
                 if (strlencmp(cmd, "on") == 0) {
-                        cmos_cmd = 0x0c;
-                        lght_cmd = 1;
+                        newstatus = 1;
                 } else if (strlencmp(cmd, "off") == 0) {
-                        cmos_cmd = 0x0d;
-                        lght_cmd = 0;
+                        newstatus = 0;
                 } else
                         return -EINVAL;
-
-                success = cmos_handle ?
-                    acpi_evalf(cmos_handle, NULL, NULL, "vd", cmos_cmd) :
-                    acpi_evalf(lght_handle, NULL, NULL, "vd", lght_cmd);
-                if (!success)
-                        return -EIO;
         }
 
-        return 0;
+        return light_set_status(newstatus);
 }
 
 static struct ibm_struct light_driver_data = {
@@ -3710,6 +3745,12 @@ enum {	/* For TPACPI_LED_OLD */
         TPACPI_LED_EC_HLMS = 0x0e,      /* EC reg to select led to command */
 };
 
+enum led_status_t {
+        TPACPI_LED_OFF = 0,
+        TPACPI_LED_ON,
+        TPACPI_LED_BLINK,
+};
+
 static enum led_access_mode led_supported;
 
 TPACPI_HANDLE(led, ec, "SLED",  /* 570 */
@@ -3718,6 +3759,69 @@ TPACPI_HANDLE(led, ec, "SLED",	/* 570 */
            "LED",               /* all others */
            );                   /* R30, R31 */
 
+static int led_get_status(unsigned int led)
+{
+        int status;
+
+        switch (led_supported) {
+        case TPACPI_LED_570:
+                if (!acpi_evalf(ec_handle,
+                                &status, "GLED", "dd", 1 << led))
+                        return -EIO;
+                return (status == 0)?
+                                TPACPI_LED_OFF :
+                                ((status == 1)?
+                                        TPACPI_LED_ON :
+                                        TPACPI_LED_BLINK);
+        default:
+                return -ENXIO;
+        }
+
+        /* not reached */
+}
+
+static int led_set_status(unsigned int led, enum led_status_t ledstatus)
+{
+        /* off, on, blink. Index is led_status_t */
+        static const int const led_sled_arg1[] = { 0, 1, 3 };
+        static const int const led_exp_hlbl[] = { 0, 0, 1 };    /* led# * */
+        static const int const led_exp_hlcl[] = { 0, 1, 1 };    /* led# * */
+        static const int const led_led_arg1[] = { 0, 0x80, 0xc0 };
+
+        int rc = 0;
+
+        switch (led_supported) {
+        case TPACPI_LED_570:
+                        /* 570 */
+                        led = 1 << led;
+                        if (!acpi_evalf(led_handle, NULL, NULL, "vdd",
+                                        led, led_sled_arg1[ledstatus]))
+                                rc = -EIO;
+                        break;
+        case TPACPI_LED_OLD:
+                        /* 600e/x, 770e, 770x, A21e, A2xm/p, T20-22, X20 */
+                        led = 1 << led;
+                        rc = ec_write(TPACPI_LED_EC_HLMS, led);
+                        if (rc >= 0)
+                                rc = ec_write(TPACPI_LED_EC_HLBL,
+                                              led * led_exp_hlbl[ledstatus]);
+                        if (rc >= 0)
+                                rc = ec_write(TPACPI_LED_EC_HLCL,
+                                               led * led_exp_hlcl[ledstatus]);
+                        break;
+        case TPACPI_LED_NEW:
+                        /* all others */
+                        if (!acpi_evalf(led_handle, NULL, NULL, "vdd",
+                                        led, led_led_arg1[ledstatus]))
+                                rc = -EIO;
+                        break;
+        default:
+                rc = -ENXIO;
+        }
+
+        return rc;
+}
+
 static int __init led_init(struct ibm_init_struct *iibm)
 {
         vdbg_printk(TPACPI_DBG_INIT, "initializing LED subdriver\n");
@@ -3743,7 +3847,9 @@ static int __init led_init(struct ibm_init_struct *iibm)
         return (led_supported != TPACPI_LED_NONE)? 0 : 1;
 }
 
-#define led_status(s) ((s) == 0 ? "off" : ((s) == 1 ? "on" : "blinking"))
+#define str_led_status(s) \
+        ((s) == TPACPI_LED_OFF ? "off" : \
+                ((s) == TPACPI_LED_ON ? "on" : "blinking"))
 
 static int led_read(char *p)
 {
@@ -3759,11 +3865,11 @@ static int led_read(char *p)
                 /* 570 */
                 int i, status;
                 for (i = 0; i < 8; i++) {
-                        if (!acpi_evalf(ec_handle,
-                                        &status, "GLED", "dd", 1 << i))
+                        status = led_get_status(i);
+                        if (status < 0)
                                 return -EIO;
                         len += sprintf(p + len, "%d:\t\t%s\n",
-                                       i, led_status(status));
+                                       i, str_led_status(status));
                 }
         }
 
@@ -3773,16 +3879,11 @@ static int led_read(char *p)
         return len;
 }
 
-/* off, on, blink */
-static const int led_sled_arg1[] = { 0, 1, 3 };
-static const int led_exp_hlbl[] = { 0, 0, 1 };  /* led# * */
-static const int led_exp_hlcl[] = { 0, 1, 1 };  /* led# * */
-static const int led_led_arg1[] = { 0, 0x80, 0xc0 };
-
 static int led_write(char *buf)
 {
         char *cmd;
-        int led, ind, ret;
+        int led, rc;
+        enum led_status_t s;
 
         if (!led_supported)
                 return -ENODEV;
@@ -3792,38 +3893,18 @@ static int led_write(char *buf)
                         return -EINVAL;
 
                 if (strstr(cmd, "off")) {
-                        ind = 0;
+                        s = TPACPI_LED_OFF;
                 } else if (strstr(cmd, "on")) {
-                        ind = 1;
+                        s = TPACPI_LED_ON;
                 } else if (strstr(cmd, "blink")) {
-                        ind = 2;
-                } else
-                        return -EINVAL;
-
-                if (led_supported == TPACPI_LED_570) {
-                        /* 570 */
-                        led = 1 << led;
-                        if (!acpi_evalf(led_handle, NULL, NULL, "vdd",
-                                        led, led_sled_arg1[ind]))
-                                return -EIO;
-                } else if (led_supported == TPACPI_LED_OLD) {
-                        /* 600e/x, 770e, 770x, A21e, A2xm/p, T20-22, X20 */
-                        led = 1 << led;
-                        ret = ec_write(TPACPI_LED_EC_HLMS, led);
-                        if (ret >= 0)
-                                ret = ec_write(TPACPI_LED_EC_HLBL,
-                                                led * led_exp_hlbl[ind]);
-                        if (ret >= 0)
-                                ret = ec_write(TPACPI_LED_EC_HLCL,
-                                                led * led_exp_hlcl[ind]);
-                        if (ret < 0)
-                                return ret;
+                        s = TPACPI_LED_BLINK;
                 } else {
-                        /* all others */
-                        if (!acpi_evalf(led_handle, NULL, NULL, "vdd",
-                                        led, led_led_arg1[ind]))
-                                return -EIO;
+                        return -EINVAL;
                 }
+
+                rc = led_set_status(led, s);
+                if (rc < 0)
+                        return rc;
         }
 
         return 0;