x86, olpc-xo1-sci: Add GPE handler and ebook switch functionality
authorDaniel Drake <dsd@laptop.org>
Sat, 25 Jun 2011 16:34:14 +0000 (17:34 +0100)
committerH. Peter Anvin <hpa@linux.intel.com>
Wed, 6 Jul 2011 21:44:38 +0000 (14:44 -0700)
The EC in the OLPC XO-1 delivers GPE events to provide various
notifications. Add the basic code for GPE/EC event processing and
enable the ebook switch, which can be used as a wakeup source.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Link: http://lkml.kernel.org/r/1309019658-1712-8-git-send-email-dsd@laptop.org
Acked-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
arch/x86/Kconfig
arch/x86/include/asm/olpc.h
arch/x86/platform/olpc/olpc-xo1-sci.c
include/linux/cs5535.h

index 66b7b9d519d53ed7c6eec2843843f43745178f89..88889106ac9b0d8b6c71a344182b6571d7de4b45 100644 (file)
@@ -2087,7 +2087,9 @@ config OLPC_XO1_SCI
        select MFD_CORE
        ---help---
          Add support for SCI-based features of the OLPC XO-1 laptop:
+          - EC-driven system wakeups
           - Power button
+          - Ebook switch
 
 endif # X86_32
 
index 0e56d01907fe0c0da34d1d1f4ab82dc42b74864d..87bdbca72f94854fd1bba2031b4ec007cd3fff72 100644 (file)
@@ -111,6 +111,7 @@ extern int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen,
 #define EC_WRITE_SCI_MASK              0x1b
 #define EC_WAKE_UP_WLAN                        0x24
 #define EC_WLAN_LEAVE_RESET            0x25
+#define EC_READ_EB_MODE                        0x2a
 #define EC_SET_SCI_INHIBIT             0x32
 #define EC_SET_SCI_INHIBIT_RELEASE     0x34
 #define EC_WLAN_ENTER_RESET            0x35
@@ -144,7 +145,7 @@ extern int olpc_ec_cmd(unsigned char cmd, unsigned char *inbuf, size_t inlen,
 #define OLPC_GPIO_SMB_CLK      14
 #define OLPC_GPIO_SMB_DATA     15
 #define OLPC_GPIO_WORKAUX      geode_gpio(24)
-#define OLPC_GPIO_LID          geode_gpio(26)
-#define OLPC_GPIO_ECSCI                geode_gpio(27)
+#define OLPC_GPIO_LID          26
+#define OLPC_GPIO_ECSCI                27
 
 #endif /* _ASM_X86_OLPC_H */
index 8fbf961dae8925a97912415a9bd15acf5d21ba5a..63f50506078b4a759b41479d7d9d7b46cf81a6c5 100644 (file)
  */
 
 #include <linux/cs5535.h>
+#include <linux/device.h>
+#include <linux/gpio.h>
 #include <linux/input.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/pm.h>
 #include <linux/mfd/core.h>
 #include <linux/suspend.h>
+#include <linux/workqueue.h>
 
 #include <asm/io.h>
 #include <asm/msr.h>
 
 static unsigned long acpi_base;
 static struct input_dev *power_button_idev;
+static struct input_dev *ebook_switch_idev;
+
 static int sci_irq;
 
+/* Report current ebook switch state through input layer */
+static void send_ebook_state(void)
+{
+       unsigned char state;
+
+       if (olpc_ec_cmd(EC_READ_EB_MODE, NULL, 0, &state, 1)) {
+               pr_err(PFX "failed to get ebook state\n");
+               return;
+       }
+
+       input_report_switch(ebook_switch_idev, SW_TABLET_MODE, state);
+       input_sync(ebook_switch_idev);
+}
+
+/*
+ * Process all items in the EC's SCI queue.
+ *
+ * This is handled in a workqueue because olpc_ec_cmd can be slow (and
+ * can even timeout).
+ *
+ * If propagate_events is false, the queue is drained without events being
+ * generated for the interrupts.
+ */
+static void process_sci_queue(bool propagate_events)
+{
+       int r;
+       u16 data;
+
+       do {
+               r = olpc_ec_sci_query(&data);
+               if (r || !data)
+                       break;
+
+               pr_debug(PFX "SCI 0x%x received\n", data);
+
+               if (data == EC_SCI_SRC_EBOOK && propagate_events)
+                       send_ebook_state();
+       } while (data);
+
+       if (r)
+               pr_err(PFX "Failed to clear SCI queue");
+}
+
+static void process_sci_queue_work(struct work_struct *work)
+{
+       process_sci_queue(true);
+}
+
+static DECLARE_WORK(sci_work, process_sci_queue_work);
+
 static irqreturn_t xo1_sci_intr(int irq, void *dev_id)
 {
        struct platform_device *pdev = dev_id;
@@ -51,6 +106,11 @@ static irqreturn_t xo1_sci_intr(int irq, void *dev_id)
                input_sync(power_button_idev);
        }
 
+       if (gpe & CS5536_GPIOM7_PME_FLAG) { /* EC GPIO */
+               cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS);
+               schedule_work(&sci_work);
+       }
+
        return IRQ_HANDLED;
 }
 
@@ -60,6 +120,19 @@ static int xo1_sci_suspend(struct platform_device *pdev, pm_message_t state)
                olpc_xo1_pm_wakeup_set(CS5536_PM_PWRBTN);
        else
                olpc_xo1_pm_wakeup_clear(CS5536_PM_PWRBTN);
+
+       if (device_may_wakeup(&ebook_switch_idev->dev))
+               olpc_ec_wakeup_set(EC_SCI_SRC_EBOOK);
+       else
+               olpc_ec_wakeup_clear(EC_SCI_SRC_EBOOK);
+
+       return 0;
+}
+
+static int xo1_sci_resume(struct platform_device *pdev)
+{
+       /* Enable all EC events */
+       olpc_ec_mask_write(EC_SCI_SRC_ALL);
        return 0;
 }
 
@@ -104,6 +177,50 @@ static int __devinit setup_sci_interrupt(struct platform_device *pdev)
        return r;
 }
 
+static int __devinit setup_ec_sci(void)
+{
+       int r;
+
+       r = gpio_request(OLPC_GPIO_ECSCI, "OLPC-ECSCI");
+       if (r)
+               return r;
+
+       gpio_direction_input(OLPC_GPIO_ECSCI);
+
+       /* Clear pending EC SCI events */
+       cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_NEGATIVE_EDGE_STS);
+       cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_POSITIVE_EDGE_STS);
+
+       /*
+        * Enable EC SCI events, and map them to both a PME and the SCI
+        * interrupt.
+        *
+        * Ordinarily, in addition to functioning as GPIOs, Geode GPIOs can
+        * be mapped to regular interrupts *or* Geode-specific Power
+        * Management Events (PMEs) - events that bring the system out of
+        * suspend. In this case, we want both of those things - the system
+        * wakeup, *and* the ability to get an interrupt when an event occurs.
+        *
+        * To achieve this, we map the GPIO to a PME, and then we use one
+        * of the many generic knobs on the CS5535 PIC to additionally map the
+        * PME to the regular SCI interrupt line.
+        */
+       cs5535_gpio_set(OLPC_GPIO_ECSCI, GPIO_EVENTS_ENABLE);
+
+       /* Set the SCI to cause a PME event on group 7 */
+       cs5535_gpio_setup_event(OLPC_GPIO_ECSCI, 7, 1);
+
+       /* And have group 7 also fire the SCI interrupt */
+       cs5535_pic_unreqz_select_high(7, sci_irq);
+
+       return 0;
+}
+
+static void free_ec_sci(void)
+{
+       gpio_free(OLPC_GPIO_ECSCI);
+}
+
 static int __devinit setup_power_button(struct platform_device *pdev)
 {
        int r;
@@ -135,6 +252,37 @@ static void free_power_button(void)
        input_free_device(power_button_idev);
 }
 
+static int __devinit setup_ebook_switch(struct platform_device *pdev)
+{
+       int r;
+
+       ebook_switch_idev = input_allocate_device();
+       if (!ebook_switch_idev)
+               return -ENOMEM;
+
+       ebook_switch_idev->name = "EBook Switch";
+       ebook_switch_idev->phys = DRV_NAME "/input1";
+       set_bit(EV_SW, ebook_switch_idev->evbit);
+       set_bit(SW_TABLET_MODE, ebook_switch_idev->swbit);
+
+       ebook_switch_idev->dev.parent = &pdev->dev;
+       device_set_wakeup_capable(&ebook_switch_idev->dev, true);
+
+       r = input_register_device(ebook_switch_idev);
+       if (r) {
+               dev_err(&pdev->dev, "failed to register ebook switch: %d\n", r);
+               input_free_device(ebook_switch_idev);
+       }
+
+       return r;
+}
+
+static void free_ebook_switch(void)
+{
+       input_unregister_device(ebook_switch_idev);
+       input_free_device(ebook_switch_idev);
+}
+
 static int __devinit xo1_sci_probe(struct platform_device *pdev)
 {
        struct resource *res;
@@ -159,10 +307,39 @@ static int __devinit xo1_sci_probe(struct platform_device *pdev)
        if (r)
                return r;
 
+       r = setup_ebook_switch(pdev);
+       if (r)
+               goto err_ebook;
+
+       r = setup_ec_sci();
+       if (r)
+               goto err_ecsci;
+
+       /* Enable PME generation for EC-generated events */
+       outl(CS5536_GPIOM7_PME_EN, acpi_base + CS5536_PM_GPE0_EN);
+
+       /* Clear pending events */
+       outl(0xffffffff, acpi_base + CS5536_PM_GPE0_STS);
+       process_sci_queue(false);
+
+       /* Initial sync */
+       send_ebook_state();
+
        r = setup_sci_interrupt(pdev);
        if (r)
-               free_power_button();
+               goto err_sci;
 
+       /* Enable all EC events */
+       olpc_ec_mask_write(EC_SCI_SRC_ALL);
+
+       return r;
+
+err_sci:
+       free_ec_sci();
+err_ecsci:
+       free_ebook_switch();
+err_ebook:
+       free_power_button();
        return r;
 }
 
@@ -170,6 +347,9 @@ static int __devexit xo1_sci_remove(struct platform_device *pdev)
 {
        mfd_cell_disable(pdev);
        free_irq(sci_irq, pdev);
+       cancel_work_sync(&sci_work);
+       free_ec_sci();
+       free_ebook_switch();
        free_power_button();
        acpi_base = 0;
        return 0;
@@ -182,6 +362,7 @@ static struct platform_driver xo1_sci_driver = {
        .probe = xo1_sci_probe,
        .remove = __devexit_p(xo1_sci_remove),
        .suspend = xo1_sci_suspend,
+       .resume = xo1_sci_resume,
 };
 
 static int __init xo1_sci_init(void)
index 6f78235cb9054fe1181e743d82b357ca2908baa9..d7e9a7f6ddb0421114be2cbc6da40a598db22cd1 100644 (file)
@@ -11,6 +11,8 @@
 #ifndef _CS5535_H
 #define _CS5535_H
 
+#include <asm/msr.h>
+
 /* MSRs */
 #define MSR_GLIU_P2D_RO0       0x10000029
 
 #define MSR_GX_GLD_MSR_CONFIG  0xC0002001
 #define MSR_GX_MSR_PADSEL      0xC0002011
 
+static inline int cs5535_pic_unreqz_select_high(unsigned int group,
+                                               unsigned int irq)
+{
+       uint32_t lo, hi;
+
+       rdmsr(MSR_PIC_ZSEL_HIGH, lo, hi);
+       lo &= ~(0xF << (group * 4));
+       lo |= (irq & 0xF) << (group * 4);
+       wrmsr(MSR_PIC_ZSEL_HIGH, lo, hi);
+       return 0;
+}
+
 /* PIC registers */
 #define CS5536_PIC_INT_SEL1    0x4d0
 #define CS5536_PIC_INT_SEL2    0x4d1
@@ -73,6 +87,7 @@
 #define CS5536_PM1_EN          0x02
 #define CS5536_PM1_CNT         0x08
 #define CS5536_PM_GPE0_STS     0x18
+#define CS5536_PM_GPE0_EN      0x1c
 
 /* CS5536_PM1_STS bits */
 #define CS5536_WAK_FLAG                (1 << 15)
 /* CS5536_PM1_EN bits */
 #define CS5536_PM_PWRBTN       (1 << 8)
 
+/* CS5536_PM_GPE0_STS bits */
+#define CS5536_GPIOM7_PME_FLAG (1 << 31)
+#define CS5536_GPIOM6_PME_FLAG (1 << 30)
+
+/* CS5536_PM_GPE0_EN bits */
+#define CS5536_GPIOM7_PME_EN   (1 << 31)
+
 /* VSA2 magic values */
 #define VSA_VRC_INDEX          0xAC1C
 #define VSA_VRC_DATA           0xAC1E