1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2012-2015 Synaptics Incorporated
4 * Copyright (C) 2016 Zodiac Inflight Innovations
5 */
6
7#include <linux/bitops.h>
8#include <linux/kernel.h>
9#include <linux/rmi.h>
10#include <linux/slab.h>
11#include "rmi_driver.h"
12
13#define F55_NAME		"rmi4_f55"
14
15/* F55 data offsets */
16#define F55_NUM_RX_OFFSET	0
17#define F55_NUM_TX_OFFSET	1
18#define F55_PHYS_CHAR_OFFSET	2
19
20/* Only read required query registers */
21#define F55_QUERY_LEN		3
22
23/* F55 capabilities */
24#define F55_CAP_SENSOR_ASSIGN	BIT(0)
25
26struct f55_data {
27	struct rmi_function *fn;
28
29	u8 qry[F55_QUERY_LEN];
30	u8 num_rx_electrodes;
31	u8 cfg_num_rx_electrodes;
32	u8 num_tx_electrodes;
33	u8 cfg_num_tx_electrodes;
34};
35
36static int rmi_f55_detect(struct rmi_function *fn)
37{
38	struct rmi_device *rmi_dev = fn->rmi_dev;
39	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
40	struct f55_data *f55;
41	int error;
42
43	f55 = dev_get_drvdata(&fn->dev);
44
45	error = rmi_read_block(fn->rmi_dev, fn->fd.query_base_addr,
46			       &f55->qry, sizeof(f55->qry));
47	if (error) {
48		dev_err(&fn->dev, "%s: Failed to query F55 properties\n",
49			__func__);
50		return error;
51	}
52
53	f55->num_rx_electrodes = f55->qry[F55_NUM_RX_OFFSET];
54	f55->num_tx_electrodes = f55->qry[F55_NUM_TX_OFFSET];
55
56	f55->cfg_num_rx_electrodes = f55->num_rx_electrodes;
57	f55->cfg_num_tx_electrodes = f55->num_rx_electrodes;
58
59	drv_data->num_rx_electrodes = f55->cfg_num_rx_electrodes;
60	drv_data->num_tx_electrodes = f55->cfg_num_rx_electrodes;
61
62	if (f55->qry[F55_PHYS_CHAR_OFFSET] & F55_CAP_SENSOR_ASSIGN) {
63		int i, total;
64		u8 buf[256];
65
66		/*
67		 * Calculate the number of enabled receive and transmit
68		 * electrodes by reading F55:Ctrl1 (sensor receiver assignment)
69		 * and F55:Ctrl2 (sensor transmitter assignment). The number of
70		 * enabled electrodes is the sum of all field entries with a
71		 * value other than 0xff.
72		 */
73		error = rmi_read_block(fn->rmi_dev,
74				       fn->fd.control_base_addr + 1,
75				       buf, f55->num_rx_electrodes);
76		if (!error) {
77			total = 0;
78			for (i = 0; i < f55->num_rx_electrodes; i++) {
79				if (buf[i] != 0xff)
80					total++;
81			}
82			f55->cfg_num_rx_electrodes = total;
83			drv_data->num_rx_electrodes = total;
84		}
85
86		error = rmi_read_block(fn->rmi_dev,
87				       fn->fd.control_base_addr + 2,
88				       buf, f55->num_tx_electrodes);
89		if (!error) {
90			total = 0;
91			for (i = 0; i < f55->num_tx_electrodes; i++) {
92				if (buf[i] != 0xff)
93					total++;
94			}
95			f55->cfg_num_tx_electrodes = total;
96			drv_data->num_tx_electrodes = total;
97		}
98	}
99
100	rmi_dbg(RMI_DEBUG_FN, &fn->dev, "F55 num_rx_electrodes: %d (raw %d)\n",
101		f55->cfg_num_rx_electrodes, f55->num_rx_electrodes);
102	rmi_dbg(RMI_DEBUG_FN, &fn->dev, "F55 num_tx_electrodes: %d (raw %d)\n",
103		f55->cfg_num_tx_electrodes, f55->num_tx_electrodes);
104
105	return 0;
106}
107
108static int rmi_f55_probe(struct rmi_function *fn)
109{
110	struct f55_data *f55;
111
112	f55 = devm_kzalloc(&fn->dev, sizeof(struct f55_data), GFP_KERNEL);
113	if (!f55)
114		return -ENOMEM;
115
116	f55->fn = fn;
117	dev_set_drvdata(&fn->dev, f55);
118
119	return rmi_f55_detect(fn);
120}
121
122struct rmi_function_handler rmi_f55_handler = {
123	.driver = {
124		.name = F55_NAME,
125	},
126	.func = 0x55,
127	.probe = rmi_f55_probe,
128};
129