[PATCH 1/3] extcon: max8997: Check the pointer of platform data toprotect null pointer error

From: Chanwoo Choi
Date: Wed Mar 13 2013 - 05:02:49 EST


This patch check the pointer of platform data to protect
kernel panic when platform data is not used and code clean.

Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Signed-off-by: Myungjoo Ham <myungjoo.ham@xxxxxxxxxxx>
---
drivers/extcon/extcon-max8997.c | 56 +++++++++++++++++++++++++----------------
1 file changed, 34 insertions(+), 22 deletions(-)

diff --git a/drivers/extcon/extcon-max8997.c b/drivers/extcon/extcon-max8997.c
index e636d95..69641bc 100644
--- a/drivers/extcon/extcon-max8997.c
+++ b/drivers/extcon/extcon-max8997.c
@@ -712,29 +712,45 @@ static int max8997_muic_probe(struct platform_device *pdev)
goto err_irq;
}

- /* Initialize registers according to platform data */
if (pdata->muic_pdata) {
- struct max8997_muic_platform_data *mdata = info->muic_pdata;
-
- for (i = 0; i < mdata->num_init_data; i++) {
- max8997_write_reg(info->muic, mdata->init_data[i].addr,
- mdata->init_data[i].data);
+ struct max8997_muic_platform_data *muic_pdata
+ = pdata->muic_pdata;
+
+ /* Initialize registers according to platform data */
+ for (i = 0; i < muic_pdata->num_init_data; i++) {
+ max8997_write_reg(info->muic,
+ muic_pdata->init_data[i].addr,
+ muic_pdata->init_data[i].data);
}
- }

- /*
- * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
- * h/w path of COMP2/COMN1 on CONTROL1 register.
- */
- if (pdata->muic_pdata->path_uart)
- info->path_uart = pdata->muic_pdata->path_uart;
- else
- info->path_uart = CONTROL1_SW_UART;
+ /*
+ * Default usb/uart path whether UART/USB or AUX_UART/AUX_USB
+ * h/w path of COMP2/COMN1 on CONTROL1 register.
+ */
+ if (muic_pdata->path_uart)
+ info->path_uart = muic_pdata->path_uart;
+ else
+ info->path_uart = CONTROL1_SW_UART;

- if (pdata->muic_pdata->path_usb)
- info->path_usb = pdata->muic_pdata->path_usb;
- else
+ if (muic_pdata->path_usb)
+ info->path_usb = muic_pdata->path_usb;
+ else
+ info->path_usb = CONTROL1_SW_USB;
+
+ /*
+ * Default delay time for detecting cable state
+ * after certain time.
+ */
+ if (muic_pdata->detcable_delay_ms)
+ delay_jiffies =
+ msecs_to_jiffies(muic_pdata->detcable_delay_ms);
+ else
+ delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
+ } else {
+ info->path_uart = CONTROL1_SW_UART;
info->path_usb = CONTROL1_SW_USB;
+ delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
+ }

/* Set initial path for UART */
max8997_muic_set_path(info, info->path_uart, true);
@@ -751,10 +767,6 @@ static int max8997_muic_probe(struct platform_device *pdev)
* driver should notify cable state to upper layer.
*/
INIT_DELAYED_WORK(&info->wq_detcable, max8997_muic_detect_cable_wq);
- if (pdata->muic_pdata->detcable_delay_ms)
- delay_jiffies = msecs_to_jiffies(pdata->muic_pdata->detcable_delay_ms);
- else
- delay_jiffies = msecs_to_jiffies(DELAY_MS_DEFAULT);
schedule_delayed_work(&info->wq_detcable, delay_jiffies);

return 0;
--
1.8.0

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