drivers/media/dvb/frontends/dib8000.c:1837 dib8000_tune() warn: variable dereferenced before check '

Hi Patrick,

FYI, the below commit triggered a smatch warning:

77e2c0f V4L/DVB (12900): DiB8000: added support for DiBcom ISDB-T/ISDB-Tsb demodulator DiB8000

+ drivers/media/dvb/frontends/dib8000.c:1837 dib8000_tune() warn: variable dereferenced before check 'state' (see line 1834)

vim +1837 drivers/media/dvb/frontends/dib8000.c

77e2c0f5 Patrick Boettcher 2009-08-17  1830  static int dib8000_tune(struct dvb_frontend *fe)
77e2c0f5 Patrick Boettcher 2009-08-17  1831  {
77e2c0f5 Patrick Boettcher 2009-08-17  1832  	struct dib8000_state *state = fe->demodulator_priv;
77e2c0f5 Patrick Boettcher 2009-08-17  1833  	int ret = 0;
77e2c0f5 Patrick Boettcher 2009-08-17  1834  	u16 value, mode = fft_to_mode(state);
77e2c0f5 Patrick Boettcher 2009-08-17  1835  
77e2c0f5 Patrick Boettcher 2009-08-17  1836  	// we are already tuned - just resuming from suspend

77e2c0f5 Patrick Boettcher 2009-08-17 @1837 if (state = NULL)
77e2c0f5 Patrick Boettcher 2009-08-17 1838 return -EINVAL;
77e2c0f5 Patrick Boettcher 2009-08-17 1839

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