2012-11-22 18:43:39

by Jun Chen

Subject: [PATCH] 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 <[email protected]>
Signed-off-by: Chen Jun <[email protected]>
---
drivers/tty/serial/ifx6x60.c | 39 +++++++++++++++++++++++++++++++++++++++
1 files changed, 39 insertions(+), 0 deletions(-)

diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 5b9bc19..a91f4cb 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 */

/**
@@ -1219,6 +1249,9 @@ 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);
}

/*
@@ -1368,6 +1401,7 @@ static void __exit ifx_spi_exit(void)
static int __init ifx_spi_init(void)
{
int result;
+ int ret;

tty_drv = alloc_tty_driver(1);
if (!tty_drv) {
@@ -1399,6 +1433,11 @@ static int __init ifx_spi_init(void)
DRVNAME, result);
tty_unregister_driver(tty_drv);
}
+
+ ret = register_reboot_notifier(&ifx_modem_reboot_notifier_block);
+ if (ret)
+ pr_err("cannot register reboot notifier (err=%d)\n", ret);
+
return result;
}

--
1.7.4.1

2012-11-22 18:31:53

by Alan

Subject: Re: [PATCH] serial: ifx6x60: Add modem power off function in the platform reboot process

On Thu, 22 Nov 2012 06:19:23 -0500
Jun Chen <[email protected]> wrote:

>
> 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.

Need to unregister the reboot notifier in the ifx_spi_exit path. If the
driver module is unloaded you leave the callback present and the kernel
will call into freed memory.

Alan

2012-11-23 03:11:29

by Jun Chen

Subject: Re: [PATCH] serial: ifx6x60: Add modem power off function in the platform reboot process

On Thu, 2012-11-22 at 11:08 +0000, Alan Cox wrote:
> On Thu, 22 Nov 2012 06:19:23 -0500
> Jun Chen <[email protected]> wrote:
>
> >
> > 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.
>
> Need to unregister the reboot notifier in the ifx_spi_exit path. If the
> driver module is unloaded you leave the callback present and the kernel
> will call into freed memory.
>
> Alan
Yes,thanks! I will update this patch again.