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1Kernel driver max1972====================3 4Author:5 6 * Vivien Didelot <vivien.didelot@savoirfairelinux.com>7 8Supported chips:9 10 * Maxim MAX19711 12 Prefix: 'max197'13 14 Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX197.pdf15 16 * Maxim MAX19917 18 Prefix: 'max199'19 20 Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX199.pdf21 22Description23-----------24 25The A/D converters MAX197, and MAX199 are both 8-Channel, Multi-Range, 5V,2612-Bit DAS with 8+4 Bus Interface and Fault Protection.27 28The available ranges for the MAX197 are {0,-5V} to 5V, and {0,-10V} to 10V,29while they are {0,-2V} to 2V, and {0,-4V} to 4V on the MAX199.30 31Platform data32-------------33 34The MAX197 platform data (defined in linux/platform_data/max197.h) should be35filled with a pointer to a conversion function, defined like::36 37 int convert(u8 ctrl);38 39ctrl is the control byte to write to start a new conversion.40On success, the function must return the 12-bit raw value read from the chip,41or a negative error code otherwise.42 43Control byte format:44 45======= ========== ============================================46Bit Name Description477,6 PD1,PD0 Clock and Power-Down modes485 ACQMOD Internal or External Controlled Acquisition494 RNG Full-scale voltage magnitude at the input503 BIP Unipolar or Bipolar conversion mode512,1,0 A2,A1,A0 Channel52======= ========== ============================================53 54Sysfs interface55---------------56 57 ============== ==============================================================58 in[0-7]_input The conversion value for the corresponding channel.59 RO60 61 in[0-7]_min The lower limit (in mV) for the corresponding channel.62 For the MAX197, it will be adjusted to -10000, -5000, or 0.63 For the MAX199, it will be adjusted to -4000, -2000, or 0.64 RW65 66 in[0-7]_max The higher limit (in mV) for the corresponding channel.67 For the MAX197, it will be adjusted to 0, 5000, or 10000.68 For the MAX199, it will be adjusted to 0, 2000, or 4000.69 RW70 ============== ==============================================================71