iio/amplifiers/hmc425a.c

26  * The LTC6373 amplifier supports configuring gain using GPIO's with the following
30  * From here, it is observed that all values are multiples of the '2' gain setting,
56 	int				(*gain_dB_to_code)(int gain, int *code);
64 	u32	gain;
71 	int gain;
74 		gain = (val * 1000) - (val2 / 1000);
76 		gain = (val * 1000) + (val2 / 1000);
78 	if (gain > inf->gain_max || gain < inf->gain_min)
83 	return st->chip_info->gain_dB_to_code(gain, code);
86 static int hmc425a_gain_dB_to_code(int gain, int *code)
88 	*code = ~((abs(gain) / 500) & 0x3F);
92 static int hmc540s_gain_dB_to_code(int gain, int *code)
94 	*code = ~((abs(gain) / 1000) & 0xF);
98 static int adrf5740_gain_dB_to_code(int gain, int *code)
100 	int temp = (abs(gain) / 2000) & 0xF;
107 static int ltc6373_gain_dB_to_code(int gain, int *code)
109 	*code = ~(DIV_ROUND_CLOSEST(gain, LTC6373_CONVERSION_CONSTANT) + 3)
118 	return st->chip_info->code_to_gain_dB(st->gain, val, val2);
149 	int gain = ((~code & LTC6373_CONVERSION_MASK) - 3) *
152 	*val = gain / 1000;
153 	*val2 = (gain % 1000) * 1000;
205 		st->gain = code;
207 		ret = hmc425a_write(indio_dev, st->gain);
261 	code = (powerdown) ? LTC6373_SHUTDOWN : st->gain;
312 		.default_gain = -0x40, /* set default gain -31.5db*/
323 		.default_gain = -0x10, /* set default gain -15.0db*/
334 		.default_gain = 0xF, /* set default gain -22.0db*/
343 		.gain_min = -12041, /* gain setting x0.25*/
344 		.gain_max = 24082,  /* gain setting x16  */
369 	st->gain = st->chip_info->default_gain;
395 		/* Set default gain */
396 		hmc425a_write(indio_dev, st->gain);