drivers/iio/proximity/sx_common.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * Copyright 2021 Google LLC.
   4  *
   5  * Code shared between most Semtech SAR sensor driver.
   6  */
   7
   8 #ifndef IIO_SX_COMMON_H
   9 #define IIO_SX_COMMON_H
  10
  11 #include <linux/iio/iio.h>
  12 #include <linux/iio/types.h>
  13 #include <linux/regulator/consumer.h>
  14 #include <linux/types.h>
  15
  16 struct device;
  17 struct i2c_client;
  18 struct regmap_config;
  19 struct sx_common_data;
  20
  21 #define SX_COMMON_REG_IRQ_SRC                           0x00
  22
  23 #define SX_COMMON_MAX_NUM_CHANNELS      4
  24 static_assert(SX_COMMON_MAX_NUM_CHANNELS < BITS_PER_LONG);
  25
  26 struct sx_common_reg_default {
  27         u8 reg;
  28         u8 def;
  29         const char *property;
  30 };
  31
  32 /**
  33  * struct sx_common_ops: function pointers needed by common code
  34  *
  35  * List functions needed by common code to gather information or configure
  36  * the sensor.
  37  *
  38  * @read_prox_data:     Function to read raw proximity data.
  39  * @check_whoami:       Set device name based on whoami register.
  40  * @init_compensation:  Function to set initial compensation.
  41  * @wait_for_sample:    When there are no physical IRQ, function to wait for a
  42  *                      sample to be ready.
  43  * @get_default_reg:    Populate the initial value for a given register.
  44  */
  45 struct sx_common_ops {
  46         int (*read_prox_data)(struct sx_common_data *data,
  47                               const struct iio_chan_spec *chan, __be16 *val);
  48         int (*check_whoami)(struct device *dev, struct iio_dev *indio_dev);
  49         int (*init_compensation)(struct iio_dev *indio_dev);
  50         int (*wait_for_sample)(struct sx_common_data *data);
  51         const struct sx_common_reg_default  *
  52                 (*get_default_reg)(struct device *dev, int idx,
  53                                    struct sx_common_reg_default *reg_def);
  54 };
  55
  56 /**
  57  * struct sx_common_chip_info: Semtech Sensor private chip information
  58  *
  59  * @reg_stat:           Main status register address.
  60  * @reg_irq_msk:        IRQ mask register address.
  61  * @reg_enable_chan:    Address to enable/disable channels.
  62  *                      Each phase presented by the sensor is an IIO channel..
  63  * @reg_reset:          Reset register address.
  64  * @mask_enable_chan:   Mask over the channels bits in the enable channel
  65  *                      register.
  66  * @stat_offset:        Offset to check phase status.
  67  * @irq_msk_offset:     Offset to enable interrupt in the IRQ mask
  68  *                      register.
  69  * @num_channels:       Number of channels.
  70  * @num_default_regs:   Number of internal registers that can be configured.
  71  *
  72  * @ops:                Private functions pointers.
  73  * @iio_channels:       Description of exposed iio channels.
  74  * @num_iio_channels:   Number of iio_channels.
  75  * @iio_info:           iio_info structure for this driver.
  76  */
  77 struct sx_common_chip_info {
  78         unsigned int reg_stat;
  79         unsigned int reg_irq_msk;
  80         unsigned int reg_enable_chan;
  81         unsigned int reg_reset;
  82
  83         unsigned int mask_enable_chan;
  84         unsigned int stat_offset;
  85         unsigned int irq_msk_offset;
  86         unsigned int num_channels;
  87         int num_default_regs;
  88
  89         struct sx_common_ops ops;
  90
  91         const struct iio_chan_spec *iio_channels;
  92         int num_iio_channels;
  93         struct iio_info iio_info;
  94 };
  95
  96 /**
  97  * struct sx_common_data: Semtech Sensor private data structure.
  98  *
  99  * @chip_info:          Structure defining sensor internals.
 100  * @mutex:              Serialize access to registers and channel configuration.
 101  * @completion:         completion object to wait for data acquisition.
 102  * @client:             I2C client structure.
 103  * @trig:               IIO trigger object.
 104  * @regmap:             Register map.
 105  * @chan_prox_stat:     Last reading of the proximity status for each channel.
 106  *                      We only send an event to user space when this changes.
 107  * @trigger_enabled:    True when the device trigger is enabled.
 108  * @buffer:             Buffer to store raw samples.
 109  * @suspend_ctrl:       Remember enabled channels and sample rate during suspend.
 110  * @chan_read:          Bit field for each raw channel enabled.
 111  * @chan_event:         Bit field for each event enabled.
 112  */
 113 struct sx_common_data {
 114         const struct sx_common_chip_info *chip_info;
 115
 116         struct mutex mutex;
 117         struct completion completion;
 118         struct i2c_client *client;
 119         struct iio_trigger *trig;
 120         struct regmap *regmap;
 121
 122         unsigned long chan_prox_stat;
 123         bool trigger_enabled;
 124
 125         /* Ensure correct alignment of timestamp when present. */
 126         struct {
 127                 __be16 channels[SX_COMMON_MAX_NUM_CHANNELS];
 128                 s64 ts __aligned(8);
 129         } buffer;
 130
 131         unsigned int suspend_ctrl;
 132         unsigned long chan_read;
 133         unsigned long chan_event;
 134 };
 135
 136 int sx_common_read_proximity(struct sx_common_data *data,
 137                              const struct iio_chan_spec *chan, int *val);
 138
 139 int sx_common_read_event_config(struct iio_dev *indio_dev,
 140                                 const struct iio_chan_spec *chan,
 141                                 enum iio_event_type type,
 142                                 enum iio_event_direction dir);
 143 int sx_common_write_event_config(struct iio_dev *indio_dev,
 144                                  const struct iio_chan_spec *chan,
 145                                  enum iio_event_type type,
 146                                  enum iio_event_direction dir, bool state);
 147
 148 int sx_common_probe(struct i2c_client *client,
 149                     const struct sx_common_chip_info *chip_info,
 150                     const struct regmap_config *regmap_config);
 151
 152 /* 3 is the number of events defined by a single phase. */
 153 extern const struct iio_event_spec sx_common_events[3];
 154
 155 #endif  /* IIO_SX_COMMON_H */