/**************************************************************************** * drivers/analog/pga11x.c * * Copyright (C) 2012 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * References: * "PGA112, PGA113, PGA116, PGA117: Zerø-Drift PROGRAMMABLE GAIN AMPLIFIER * with MUX", SBOS424B, March 2008, Revised September 2008, Texas * Instruments Incorporated" * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #if defined(CONFIG_ADC) && defined(CONFIG_ADC_PGA11X) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* The PGA112/PGA113 have a three-wire SPI digital interface; the * PGA116/PGA117 have a four-wire SPI digital interface. The PGA116/117 also * have daisy-chain capability (The PGA112/PGA113 can be used as the last device * in a daisy-chain as shown if write-only communication is acceptable). */ /* PGA11x commands (PGA112/PGA113) */ #define PGA11X_CMD_READ 0x6a00 #define PGA11X_CMD_WRITE 0x2a00 #define PGA11X_CMD_NOOP 0x0000 #define PGA11X_CMD_SDN_DIS 0xe100 #define PGA11X_CMD_SDN_EN 0xe1f1 /* SPI Daisy-Chain Commands (PGA116/PGA117) */ #define PGA11X_DCCMD_SELECTOR 0x8000 #define PGA11X_DCCMD_NOOP (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_NOOP) #define PGA11X_DCCMD_SDN_DIS (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_SDN_DIS) #define PGA11X_DCCMD_SDN_EN (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_SDN_EN) #define PGA11X_DCCMD_READ (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_READ) #define PGA11X_DCCMD_WRITE (PGA11X_DCCMD_SELECTOR | PGA11X_CMD_WRITE) /* Write command Gain Selection Bits (PGA112/PGA113) * * the PGA112 and PGA116 provide binary gain selections (1, 2, 4, 8, 16, 32, * 64, 128); the PGA113 and PGA117 provide scope gain selections (1, 2, 5, 10, * 20, 50, 100, 200). */ #define PGA11X_GAIN_SHIFT (4) /* Bits 4-7: Gain Selection Bits */ #define PGA11X_GAIN_MASK (15 << PGA11X_GAIN_SHIFT) /* Write command Mux Channel Selection Bits * * The PGA112/PGA113 have a two-channel input MUX; the PGA116/PGA117 have a * 10-channel input MUX. */ #define PGA11X_CHAN_SHIFT (0) /* Bits 0-3: Channel Selection Bits */ #define PGA11X_CHAN_MASK (15 << PGA11X_CHAN_SHIFT) /* Other definitions ********************************************************/ #define SPI_DUMMY 0xff /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: pga11x_configure * * Description: * Configure the SPI bus as needed for the PGA11x device. * * Returned Value: * None * ****************************************************************************/ static void pga11x_configure(FAR struct spi_dev_s *spi) { spiinfo("MODE: %d BITS: 8 Frequency: %d\n", CONFIG_PGA11X_SPIMODE, CONFIG_PGA11X_SPIFREQUENCY); /* Call the setfrequency, setbits, and setmode methods to make sure that * the SPI is properly configured for the device. */ SPI_SETMODE(spi, CONFIG_PGA11X_SPIMODE); SPI_SETBITS(spi, 8); (void)SPI_HWFEATURES(spi, 0); (void)SPI_SETFREQUENCY(spi, CONFIG_PGA11X_SPIFREQUENCY); } /**************************************************************************** * Name: pga11x_lock * * Description: * Lock the SPI bus and configure it as needed for the PGA11x device. * * Returned Value: * None * ****************************************************************************/ static void pga11x_lock(FAR struct spi_dev_s *spi) { spiinfo("Locking\n"); /* On SPI busses where there are multiple devices, it will be necessary to * lock SPI to have exclusive access to the busses for a sequence of * transfers. The bus should be locked before the chip is selected. * * This is a blocking call and will not return until we have exclusiv access to * the SPI buss. We will retain that exclusive access until the bus is unlocked. */ SPI_LOCK(spi, true); /* After locking the SPI bus, the we also need call the setfrequency, setbits, and * setmode methods to make sure that the SPI is properly configured for the device. * If the SPI buss is being shared, then it may have been left in an incompatible * state. */ pga11x_configure(spi); } /**************************************************************************** * Name: pga11x_unlock * * Description: * Lock the SPI bus and configure it as needed for the PGA11x device. * * Returned Value: * None * ****************************************************************************/ static inline void pga11x_unlock(FAR struct spi_dev_s *spi) { spiinfo("Unlocking\n"); SPI_LOCK(spi, false); } /**************************************************************************** * Name: pga11x_send16 * * Description: * Send 16 bits of data, ignoring any returned data * * Input Parameters: * spi - PGA11X driver instance * word - The data to send * * Returned Value: * None * * Assumptions: * The bus is locked and the device is selected * ****************************************************************************/ static void pga11x_send16(FAR struct spi_dev_s *spi, uint16_t word) { spiinfo("Send %04x\n", word); /* The logical interface is 16-bits wide. However, this driver uses a * 8-bit configuration for greaer portability. * * Send the MS byte first. Then the LS byte. */ SPI_SEND(spi, word >> 8); SPI_SEND(spi, word & 0xff); } /**************************************************************************** * Name: pga11x_recv16 * * Description: * Receive 16 bits of data. * * Input Parameters: * spi - PGA11X driver instance * * Returned Value: * The received 16-bit value * * Assumptions: * The bus is locked and the device is selected * ****************************************************************************/ static uint16_t pga11x_recv16(FAR struct spi_dev_s *spi) { uint8_t msb; uint8_t lsb; /* The logical interface is 16-bits wide. However, this driver uses a * 8-bit configuration for greaer portability. * * Send a dummy byte and receive MS byte first. Then the LS byte. */ msb = SPI_SEND(spi, SPI_DUMMY); lsb = SPI_SEND(spi, SPI_DUMMY); spiinfo("Received %02x %02x\n", msb, lsb); return ((uint16_t)msb << 8) | (uint16_t)lsb; } /**************************************************************************** * Name: pga11x_write * * Description: * Send a 16-bit command. * * Input Parameters: * spi - PGA11X driver instance * cmd - PGA11X command (non-daisy chained) * u1cmd - PGA11X U1 command (daisy chained) * u2cmd - PGA11X U2 command (daisy chained) * * Returned Value: * The received 16-bit value * * Assumptions: * The device is NOT selected and the NOT bus is locked. * ****************************************************************************/ #ifndef CONFIG_PGA11X_DAISYCHAIN static void pga11x_write(FAR struct spi_dev_s *spi, uint16_t cmd) { spiinfo("cmd %04x\n", cmd); /* Lock, select, send the 16-bit command, de-select, and un-lock. */ pga11x_lock(spi); SPI_SELECT(spi, SPIDEV_MUX, true); pga11x_send16(spi, cmd); SPI_SELECT(spi, SPIDEV_MUX, false); pga11x_unlock(spi); } #else static void pga11x_write(FAR struct spi_dev_s *spi, uint16_t u1cmd, uint16_t u2cmd) { spiinfo("U1 cmd: %04x U2 cmd: %04x\n", u1cmd, u2cmd); /* Lock, select, send the U2 16-bit command, the U1 16-bit command, de-select, * and un-lock. */ pga11x_lock(spi); SPI_SELECT(spi, SPIDEV_MUX, true); pga11x_send16(spi, u2cmd); pga11x_send16(spi, u1cmd); SPI_SELECT(spi, SPIDEV_MUX, false); pga11x_unlock(spi); } #endif /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: pga11x_initialize * * Description: * Initialize the PGA117 amplifier/multiplexer(s). * * Input Parameters: * spi - An SPI "bottom half" device driver instance * * Returned Value: * On success, a non-NULL opaque handle is returned; a NULL is returned * on any failure. This handle may be used with the other PGA117 interface * functions to control the multiplexer * ****************************************************************************/ PGA11X_HANDLE pga11x_initialize(FAR struct spi_dev_s *spi) { spiinfo("Entry\n"); /* No Special state is required, just return the SPI driver instance as * the handle. This gives us a place to extend functionality in the * future if neccessary. */ return (PGA11X_HANDLE)spi; } /**************************************************************************** * Name: pga11x_select * * Description: * Select an input channel and gain for all PGA11xs. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_select() configures * both chips in the daisy-chain. pga11x_uselect() is provided to support * configuring the parts in the daisychain independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * settings - New channel and gain settings * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ int pga11x_select(PGA11X_HANDLE handle, FAR const struct pga11x_settings_s *settings) { #ifndef CONFIG_PGA11X_DAISYCHAIN FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; uint16_t cmd; DEBUGASSERT(handle && settings); spiinfo("channel: %d gain: %d\n", settings->channel, settings->gain); /* Format the command */ cmd = PGA11X_CMD_WRITE | ((uint16_t)settings->channel << PGA11X_CHAN_SHIFT) | ((uint16_t)settings->gain << PGA11X_GAIN_SHIFT); /* Send the command */ pga11x_write(spi, cmd); return OK; #else FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; uint16_t u1cmd; uint16_t u2cmd; DEBUGASSERT(handle && settings); spiinfo("U1 channel: %d gain: %d\n", settings->u1.channel, settings->u1.gain); spiinfo("U1 channel: %d gain: %d\n", settings->u1.channel, settings->u1.gain); /* Format the commands */ u1cmd = PGA11X_CMD_WRITE | ((uint16_t)settings->u1.channel << PGA11X_CHAN_SHIFT) | ((uint16_t)settings->u1.gain << PGA11X_GAIN_SHIFT); u2cmd = PGA11X_DCCMD_WRITE | ((uint16_t)settings->u2.channel << PGA11X_CHAN_SHIFT) | ((uint16_t)settings->u2.gain << PGA11X_GAIN_SHIFT); /* Send the command */ pga11x_write(spi, u1cmd, u2cmd); return OK; #endif } /**************************************************************************** * Name: pga11x_uselect * * Description: * Select an input channel and gain for one PGA11x. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_uselect() configures * one chips in the daisy-chain. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * pos - Position of the chip in the daisy chain (0 or 1) * settings - New channel and gain settings * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ #ifdef CONFIG_PGA11X_DAISYCHAIN int pga11x_uselect(PGA11X_HANDLE handle, int pos, FAR const struct pga11x_usettings_s *settings) { FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; uint16_t u1cmd; uint16_t u2cmd; spiinfo("channel: %d gain: %d\n", settings->channel, settings->gain); DEBUGASSERT(handle); /* Format the commands */ if (pos == 0) { u1cmd = PGA11X_CMD_WRITE | ((uint16_t)settings->channel << PGA11X_CHAN_SHIFT) | ((uint16_t)settings->gain << PGA11X_GAIN_SHIFT); u2cmd = PGA11X_DCCMD_NOOP; } else /* if (pos == 1) */ { u1cmd = PGA11X_CMD_NOOP; u2cmd = PGA11X_DCCMD_WRITE | ((uint16_t)settings->channel << PGA11X_CHAN_SHIFT) | ((uint16_t)settings->gain << PGA11X_GAIN_SHIFT); } /* Send the command */ pga11x_write(spi, u1cmd, u2cmd); return OK; } #endif /**************************************************************************** * Name: pga11x_read * * Description: * Read from all PGA117 amplifier/multiplexers. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_read() reads from * both chips in the daisy-chain. pga11x_uread() is provided to support * accessing the parts independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * settings - Returned channel and gain settings * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ int pga11x_read(PGA11X_HANDLE handle, FAR struct pga11x_settings_s *settings) { #ifdef CONFIG_PGA11X_DAISYCHAIN FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; uint16_t u1value; uint16_t u2value; spiinfo("Entry\n"); DEBUGASSERT(handle && settings); /* Lock the bus and read the configuration */ pga11x_lock(spi); /* Select, send the 16-bit command, the 16-bit daisy-chain command, and * then de-select the part. I do not know if de-selection between word * transfers is required. However, it is shown in the timing diagrams * for the part. */ SPI_SELECT(spi, SPIDEV_MUX, true); pga11x_send16(spi, PGA11X_CMD_READ); pga11x_send16(spi, PGA11X_DCCMD_READ); SPI_SELECT(spi, SPIDEV_MUX, false); /* Re-select, get the returned values, de-select, and unlock */ SPI_SELECT(spi, SPIDEV_MUX, true); u2value = pga11x_recv16(spi); u1value = pga11x_recv16(spi); SPI_SELECT(spi, SPIDEV_MUX, false); pga11x_unlock(spi); /* Decode the returned value */ spiinfo("Returning %04x %04x\n", u2value, u1value); settings->u1.channel = (uint8_t)((u1value & PGA11X_CHAN_MASK) >> PGA11X_CHAN_SHIFT); settings->u1.gain = (uint8_t)((u1value & PGA11X_GAIN_MASK) >> PGA11X_GAIN_SHIFT); settings->u2.channel = (uint8_t)((u2value & PGA11X_CHAN_MASK) >> PGA11X_CHAN_SHIFT); settings->u2.gain = (uint8_t)((u2value & PGA11X_GAIN_MASK) >> PGA11X_GAIN_SHIFT); return OK; #else FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; uint16_t value; spiinfo("Entry\n"); DEBUGASSERT(handle); /* Lock the bus and read the configuration */ pga11x_lock(spi); /* Select, send the 16-bit PGA11X_CMD_READ command, and de-select. I do * not know if de-selection between word transfers is required. However, * it is shown in the timing diagrams for the part. */ SPI_SELECT(spi, SPIDEV_MUX, true); pga11x_send16(spi, PGA11X_CMD_READ); SPI_SELECT(spi, SPIDEV_MUX, false); /* Re-select, get the returned value, de-select, and unlock */ SPI_SELECT(spi, SPIDEV_MUX, true); value = pga11x_recv16(spi); SPI_SELECT(spi, SPIDEV_MUX, false); pga11x_unlock(spi); /* Decode the returned value */ spiinfo("Returning: %04x\n", value); settings->channel = (uint8_t)((value & PGA11X_CHAN_MASK) >> PGA11X_CHAN_SHIFT); settings->gain = (uint8_t)((value & PGA11X_GAIN_MASK) >> PGA11X_GAIN_SHIFT); return OK; #endif } /**************************************************************************** * Name: pga11x_uread * * Description: * Read from one PGA117 amplifier/multiplexer. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_read() reads * the parts independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * pos - Position of the chip in the daisy chain (0 or 1) * settings - Returned channel and gain settings * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ #ifdef CONFIG_PGA11X_DAISYCHAIN int pga11x_uread(PGA11X_HANDLE handle, int pos, FAR struct pga11x_usettings_s *settings) { struct pga11x_settings_s both; int ret = pga11x_read(handle, &both); if (ret == OK) { if (pos == 0) { settings->channel = both.u1.channel; settings->gain = both.u1.gain; } else /* if (pos == 1) */ { settings->channel = both.u2.channel; settings->gain = both.u2.gain; } } return ret; } #endif /**************************************************************************** * Name: pga11x_shutdown * * Description: * Put all PGA11x's in shutdown down mode. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_shutdown() controls * both chips in the daisy-chain. pga11x_ushutdown() is provided to * control the parts independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ int pga11x_shutdown(PGA11X_HANDLE handle) { FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; spiinfo("Entry\n"); DEBUGASSERT(handle); /* Enter shutdown mode by issuing an SDN_EN command */ #ifdef CONFIG_PGA11X_DAISYCHAIN pga11x_write(spi, PGA11X_CMD_SDN_EN, PGA11X_DCCMD_SDN_EN); #else pga11x_write(spi, PGA11X_CMD_SDN_EN); #endif return OK; } /**************************************************************************** * Name: pga11x_ushutdown * * Description: * Put one PGA11x in shutdown down mode. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_ushutdown() is * provided to shutdown the parts independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * pos - Position of the chip in the daisy chain (0 or 1) * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ #ifdef CONFIG_PGA11X_DAISYCHAIN int pga11x_ushutdown(PGA11X_HANDLE handle, int pos) { FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; spiinfo("Entry\n"); DEBUGASSERT(handle); /* Enter shutdown mode by issuing an SDN_EN command */ if (pos == 0) { pga11x_write(spi, PGA11X_CMD_SDN_EN, PGA11X_DCCMD_NOOP); } else { pga11x_write(spi, PGA11X_CMD_NOOP, PGA11X_DCCMD_SDN_EN); } return OK; } #endif /**************************************************************************** * Name: pga11x_enable * * Description: * Take all PGA11x's out of shutdown down mode. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_enable() controls * both chips in the daisy-chain. pga11x_uenable() is provided to * control the parts independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ int pga11x_enable(PGA11X_HANDLE handle) { FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; spiinfo("Entry\n"); DEBUGASSERT(handle); /* Lock the bus and send the shutdown disable command. Shutdown mode is * cleared (returned to the last valid write configuration) by the SDN_DIS * command or by any valid Write command */ #ifdef CONFIG_PGA11X_DAISYCHAIN pga11x_write(spi, PGA11X_CMD_SDN_DIS, PGA11X_DCCMD_SDN_DIS); #else pga11x_write(spi, PGA11X_CMD_SDN_DIS); #endif return OK; } /**************************************************************************** * Name: pga11x_uenable * * Description: * Take one PGA11x out of shutdown down mode. * * If CONFIG_PGA11X_DAISYCHAIN is defined, then pga11x_uenable() is * provided to enable the parts independently. * * Input Parameters: * spi - An SPI "bottom half" device driver instance * pos - Position of the chip in the daisy chain (0 or 1) * * Returned Value: * Zero on sucess; a negated errno value on failure. * ****************************************************************************/ #ifdef CONFIG_PGA11X_DAISYCHAIN int pga11x_uenable(PGA11X_HANDLE handle, int pos) { FAR struct spi_dev_s *spi = (FAR struct spi_dev_s *)handle; spiinfo("Entry\n"); DEBUGASSERT(handle); /* Enter shutdown mode by issuing an SDN_EN command */ if (pos == 0) { pga11x_write(spi, PGA11X_CMD_SDN_DIS, PGA11X_DCCMD_NOOP); } else { pga11x_write(spi, PGA11X_CMD_NOOP, PGA11X_DCCMD_SDN_DIS); } return OK; } #endif #endif /* CONFIG_ADC && CONFIG_ADC_PGA11X */