drivers/input/rmi4/rmi_f55.c

   1 /*
   2  * Copyright (c) 2012-2015 Synaptics Incorporated
   3  * Copyright (C) 2016 Zodiac Inflight Innovations
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 as published by
   7  * the Free Software Foundation.
   8  */
   9
  10 #include <linux/bitops.h>
  11 #include <linux/kernel.h>
  12 #include <linux/rmi.h>
  13 #include <linux/slab.h>
  14 #include "rmi_driver.h"
  15
  16 #define F55_NAME                "rmi4_f55"
  17
  18 /* F55 data offsets */
  19 #define F55_NUM_RX_OFFSET       0
  20 #define F55_NUM_TX_OFFSET       1
  21 #define F55_PHYS_CHAR_OFFSET    2
  22
  23 /* Only read required query registers */
  24 #define F55_QUERY_LEN           3
  25
  26 /* F55 capabilities */
  27 #define F55_CAP_SENSOR_ASSIGN   BIT(0)
  28
  29 struct f55_data {
  30         struct rmi_function *fn;
  31
  32         u8 qry[F55_QUERY_LEN];
  33         u8 num_rx_electrodes;
  34         u8 cfg_num_rx_electrodes;
  35         u8 num_tx_electrodes;
  36         u8 cfg_num_tx_electrodes;
  37 };
  38
  39 static int rmi_f55_detect(struct rmi_function *fn)
  40 {
  41         struct rmi_device *rmi_dev = fn->rmi_dev;
  42         struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
  43         struct f55_data *f55;
  44         int error;
  45
  46         f55 = dev_get_drvdata(&fn->dev);
  47
  48         error = rmi_read_block(fn->rmi_dev, fn->fd.query_base_addr,
  49                                &f55->qry, sizeof(f55->qry));
  50         if (error) {
  51                 dev_err(&fn->dev, "%s: Failed to query F55 properties\n",
  52                         __func__);
  53                 return error;
  54         }
  55
  56         f55->num_rx_electrodes = f55->qry[F55_NUM_RX_OFFSET];
  57         f55->num_tx_electrodes = f55->qry[F55_NUM_TX_OFFSET];
  58
  59         f55->cfg_num_rx_electrodes = f55->num_rx_electrodes;
  60         f55->cfg_num_tx_electrodes = f55->num_rx_electrodes;
  61
  62         drv_data->num_rx_electrodes = f55->cfg_num_rx_electrodes;
  63         drv_data->num_tx_electrodes = f55->cfg_num_rx_electrodes;
  64
  65         if (f55->qry[F55_PHYS_CHAR_OFFSET] & F55_CAP_SENSOR_ASSIGN) {
  66                 int i, total;
  67                 u8 buf[256];
  68
  69                 /*
  70                  * Calculate the number of enabled receive and transmit
  71                  * electrodes by reading F55:Ctrl1 (sensor receiver assignment)
  72                  * and F55:Ctrl2 (sensor transmitter assignment). The number of
  73                  * enabled electrodes is the sum of all field entries with a
  74                  * value other than 0xff.
  75                  */
  76                 error = rmi_read_block(fn->rmi_dev,
  77                                        fn->fd.control_base_addr + 1,
  78                                        buf, f55->num_rx_electrodes);
  79                 if (!error) {
  80                         total = 0;
  81                         for (i = 0; i < f55->num_rx_electrodes; i++) {
  82                                 if (buf[i] != 0xff)
  83                                         total++;
  84                         }
  85                         f55->cfg_num_rx_electrodes = total;
  86                         drv_data->num_rx_electrodes = total;
  87                 }
  88
  89                 error = rmi_read_block(fn->rmi_dev,
  90                                        fn->fd.control_base_addr + 2,
  91                                        buf, f55->num_tx_electrodes);
  92                 if (!error) {
  93                         total = 0;
  94                         for (i = 0; i < f55->num_tx_electrodes; i++) {
  95                                 if (buf[i] != 0xff)
  96                                         total++;
  97                         }
  98                         f55->cfg_num_tx_electrodes = total;
  99                         drv_data->num_tx_electrodes = total;
 100                 }
 101         }
 102
 103         rmi_dbg(RMI_DEBUG_FN, &fn->dev, "F55 num_rx_electrodes: %d (raw %d)\n",
 104                 f55->cfg_num_rx_electrodes, f55->num_rx_electrodes);
 105         rmi_dbg(RMI_DEBUG_FN, &fn->dev, "F55 num_tx_electrodes: %d (raw %d)\n",
 106                 f55->cfg_num_tx_electrodes, f55->num_tx_electrodes);
 107
 108         return 0;
 109 }
 110
 111 static int rmi_f55_probe(struct rmi_function *fn)
 112 {
 113         struct f55_data *f55;
 114
 115         f55 = devm_kzalloc(&fn->dev, sizeof(struct f55_data), GFP_KERNEL);
 116         if (!f55)
 117                 return -ENOMEM;
 118
 119         f55->fn = fn;
 120         dev_set_drvdata(&fn->dev, f55);
 121
 122         return rmi_f55_detect(fn);
 123 }
 124
 125 struct rmi_function_handler rmi_f55_handler = {
 126         .driver = {
 127                 .name = F55_NAME,
 128         },
 129         .func = 0x55,
 130         .probe = rmi_f55_probe,
 131 };