serial: ifx6x60: Add modem power off function in the platform reboot process

This patch add modem power off function in the reboot process according registering
reboot callback to the reboot_notifier_list. Also realizing the spi shutdown function.

Signed-off-by: Bi Chao <chao.bi@intel.com>
Signed-off-by: Chen Jun <jun.d.chen@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 53 insertions, 3 deletions

diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 6356dba49e6c..675d94ab0aff 100644
--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -60,6 +60,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/spi/ifx_modem.h>
 #include <linux/delay.h>
+#include <linux/reboot.h>
 
 #include "ifx6x60.h"
 
@@ -72,8 +73,14 @@
 #define IFX_SPI_HEADER_0                (-1)
 #define IFX_SPI_HEADER_F                (-2)
 
+#define PO_POST_DELAY           200
+#define IFX_MDM_RST_PMU 4
+
 /* forward reference */
 static void ifx_spi_handle_srdy(struct ifx_spi_device *ifx_dev);
+static int ifx_modem_reboot_callback(struct notifier_block *nfb,
+                                unsigned long event, void *data);
+static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev);
 
 /* local variables */
 static int spi_bpw = 16;                /* 8, 16 or 32 bit word length */
@@ -81,6 +88,29 @@ static struct tty_driver *tty_drv;
 static struct ifx_spi_device *saved_ifx_dev;
 static struct lock_class_key ifx_spi_key;
 
+static struct notifier_block ifx_modem_reboot_notifier_block = {
+        .notifier_call = ifx_modem_reboot_callback,
+};
+
+static int ifx_modem_power_off(struct ifx_spi_device *ifx_dev)
+{
+        gpio_set_value(IFX_MDM_RST_PMU, 1);
+        msleep(PO_POST_DELAY);
+
+        return 0;
+}
+
+static int ifx_modem_reboot_callback(struct notifier_block *nfb,
+                                 unsigned long event, void *data)
+{
+        if (saved_ifx_dev)
+                ifx_modem_power_off(saved_ifx_dev);
+        else
+                pr_warn("no ifx modem active;\n");
+
+        return NOTIFY_OK;
+}
+
 /* GPIO/GPE settings */
 
 /**
@@ -1287,6 +1317,9 @@ static int ifx_spi_spi_remove(struct spi_device *spi)
 
 static void ifx_spi_spi_shutdown(struct spi_device *spi)
 {
+        struct ifx_spi_device *ifx_dev = spi_get_drvdata(spi);
+
+        ifx_modem_power_off(ifx_dev);
 }
 
 /*
@@ -1422,7 +1455,9 @@ static void __exit ifx_spi_exit(void)
 {
         /* unregister */
         tty_unregister_driver(tty_drv);
+        put_tty_driver(tty_drv);
         spi_unregister_driver((void *)&ifx_spi_driver);
+        unregister_reboot_notifier(&ifx_modem_reboot_notifier_block);
 }
 
 /**
@@ -1457,16 +1492,31 @@ static int __init ifx_spi_init(void)
         if (result) {
                 pr_err("%s: tty_register_driver failed(%d)",
                         DRVNAME, result);
-                put_tty_driver(tty_drv);
-                return result;
+                goto err_free_tty;
         }
 
         result = spi_register_driver((void *)&ifx_spi_driver);
         if (result) {
                 pr_err("%s: spi_register_driver failed(%d)",
                         DRVNAME, result);
-                tty_unregister_driver(tty_drv);
+                goto err_unreg_tty;
+        }
+
+        result = register_reboot_notifier(&ifx_modem_reboot_notifier_block);
+        if (result) {
+                pr_err("%s: register ifx modem reboot notifier failed(%d)",
+                        DRVNAME, result);
+                goto err_unreg_spi;
         }
+
+        return 0;
+err_unreg_spi:
+        spi_unregister_driver((void *)&ifx_spi_driver);
+err_unreg_tty:
+        tty_unregister_driver(tty_drv);
+err_free_tty:
+        put_tty_driver(tty_drv);
+
         return result;
 }