[media] mxl111sf: reduce stack usage in init function
authorArnd Bergmann <arnd@arndb.de>
Thu, 2 Feb 2017 14:53:07 +0000 (12:53 -0200)
committerMauro Carvalho Chehab <mchehab@s-opensource.com>
Fri, 3 Mar 2017 10:21:48 +0000 (07:21 -0300)
mxl111sf uses a lot of kernel stack memory as it puts an i2c_client
structure on the stack:

drivers/media/usb/dvb-usb-v2/mxl111sf.c: In function 'mxl111sf_init':
drivers/media/usb/dvb-usb-v2/mxl111sf.c:953:1: error: the frame size of 1248 bytes is larger than 1152 bytes [-Werror=frame-larger-than=]

We can avoid doing this by open-coding the call to i2c_transfer()
instead of calling tveeprom_read(), and not passing an i2c_client
pointer to tveeprom_hauppauge_analog(), which would ignore that
anyway.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
drivers/media/usb/dvb-usb-v2/mxl111sf.c

index 80c6359..60bc5cc 100644 (file)
@@ -919,7 +919,12 @@ static int mxl111sf_init(struct dvb_usb_device *d)
        struct mxl111sf_state *state = d_to_priv(d);
        int ret;
        static u8 eeprom[256];
-       struct i2c_client c;
+       u8 reg = 0;
+       struct i2c_msg msg[2] = {
+               { .addr = 0xa0 >> 1, .len = 1, .buf = &reg },
+               { .addr = 0xa0 >> 1, .flags = I2C_M_RD,
+                 .len = sizeof(eeprom), .buf = eeprom },
+       };
 
        ret = get_chip_info(state);
        if (mxl_fail(ret))
@@ -930,13 +935,10 @@ static int mxl111sf_init(struct dvb_usb_device *d)
        if (state->chip_rev > MXL111SF_V6)
                mxl111sf_config_pin_mux_modes(state, PIN_MUX_TS_SPI_IN_MODE_1);
 
-       c.adapter = &d->i2c_adap;
-       c.addr = 0xa0 >> 1;
-
-       ret = tveeprom_read(&c, eeprom, sizeof(eeprom));
+       ret = i2c_transfer(&d->i2c_adap, msg, 2);
        if (mxl_fail(ret))
                return 0;
-       tveeprom_hauppauge_analog(&c, &state->tv, (0x84 == eeprom[0xa0]) ?
+       tveeprom_hauppauge_analog(NULL, &state->tv, (0x84 == eeprom[0xa0]) ?
                        eeprom + 0xa0 : eeprom + 0x80);
 #if 0
        switch (state->tv.model) {