xref: /openbmc/linux/drivers/input/rmi4/rmi_f3a.c (revision 31e67366)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2012-2020 Synaptics Incorporated
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/rmi.h>
8 #include <linux/input.h>
9 #include <linux/slab.h>
10 #include "rmi_driver.h"
11 
12 #define RMI_F3A_MAX_GPIO_COUNT		128
13 #define RMI_F3A_MAX_REG_SIZE		DIV_ROUND_UP(RMI_F3A_MAX_GPIO_COUNT, 8)
14 
15 /* Defs for Query 0 */
16 #define RMI_F3A_GPIO_COUNT		0x7F
17 
18 #define RMI_F3A_DATA_REGS_MAX_SIZE	RMI_F3A_MAX_REG_SIZE
19 
20 #define TRACKSTICK_RANGE_START		3
21 #define TRACKSTICK_RANGE_END		6
22 
23 struct f3a_data {
24 	/* Query Data */
25 	u8 gpio_count;
26 
27 	u8 register_count;
28 
29 	u8 data_regs[RMI_F3A_DATA_REGS_MAX_SIZE];
30 	u16 *gpio_key_map;
31 
32 	struct input_dev *input;
33 
34 	struct rmi_function *f03;
35 	bool trackstick_buttons;
36 };
37 
38 static void rmi_f3a_report_button(struct rmi_function *fn,
39 				  struct f3a_data *f3a, unsigned int button)
40 {
41 	u16 key_code = f3a->gpio_key_map[button];
42 	bool key_down = !(f3a->data_regs[0] & BIT(button));
43 
44 	if (f3a->trackstick_buttons &&
45 		button >= TRACKSTICK_RANGE_START &&
46 		button <= TRACKSTICK_RANGE_END) {
47 		rmi_f03_overwrite_button(f3a->f03, key_code, key_down);
48 	} else {
49 		rmi_dbg(RMI_DEBUG_FN, &fn->dev,
50 			"%s: call input report key (0x%04x) value (0x%02x)",
51 			__func__, key_code, key_down);
52 		input_report_key(f3a->input, key_code, key_down);
53 	}
54 }
55 
56 static irqreturn_t rmi_f3a_attention(int irq, void *ctx)
57 {
58 	struct rmi_function *fn = ctx;
59 	struct f3a_data *f3a = dev_get_drvdata(&fn->dev);
60 	struct rmi_driver_data *drvdata = dev_get_drvdata(&fn->rmi_dev->dev);
61 	int error;
62 	int i;
63 
64 	if (drvdata->attn_data.data) {
65 		if (drvdata->attn_data.size < f3a->register_count) {
66 			dev_warn(&fn->dev,
67 				 "F3A interrupted, but data is missing\n");
68 			return IRQ_HANDLED;
69 		}
70 		memcpy(f3a->data_regs, drvdata->attn_data.data,
71 			f3a->register_count);
72 		drvdata->attn_data.data += f3a->register_count;
73 		drvdata->attn_data.size -= f3a->register_count;
74 	} else {
75 		error = rmi_read_block(fn->rmi_dev, fn->fd.data_base_addr,
76 					f3a->data_regs, f3a->register_count);
77 		if (error) {
78 			dev_err(&fn->dev,
79 				"%s: Failed to read F3a data registers: %d\n",
80 				__func__, error);
81 			return IRQ_RETVAL(error);
82 		}
83 	}
84 
85 	for (i = 0; i < f3a->gpio_count; i++)
86 		if (f3a->gpio_key_map[i] != KEY_RESERVED)
87 			rmi_f3a_report_button(fn, f3a, i);
88 	if (f3a->trackstick_buttons)
89 		rmi_f03_commit_buttons(f3a->f03);
90 
91 	return IRQ_HANDLED;
92 }
93 
94 static int rmi_f3a_config(struct rmi_function *fn)
95 {
96 	struct f3a_data *f3a = dev_get_drvdata(&fn->dev);
97 	struct rmi_driver *drv = fn->rmi_dev->driver;
98 	const struct rmi_device_platform_data *pdata =
99 			rmi_get_platform_data(fn->rmi_dev);
100 
101 	if (!f3a)
102 		return 0;
103 
104 	if (pdata->gpio_data.trackstick_buttons) {
105 		/* Try [re-]establish link to F03. */
106 		f3a->f03 = rmi_find_function(fn->rmi_dev, 0x03);
107 		f3a->trackstick_buttons = f3a->f03 != NULL;
108 	}
109 
110 	drv->set_irq_bits(fn->rmi_dev, fn->irq_mask);
111 
112 	return 0;
113 }
114 
115 static bool rmi_f3a_is_valid_button(int button, struct f3a_data *f3a,
116 					u8 *query1_regs, u8 *ctrl1_regs)
117 {
118 	/* gpio exist && direction input */
119 	return (query1_regs[0] & BIT(button)) && !(ctrl1_regs[0] & BIT(button));
120 }
121 
122 static int rmi_f3a_map_gpios(struct rmi_function *fn, struct f3a_data *f3a,
123 				u8 *query1_regs, u8 *ctrl1_regs)
124 {
125 	const struct rmi_device_platform_data *pdata =
126 			rmi_get_platform_data(fn->rmi_dev);
127 	struct input_dev *input = f3a->input;
128 	unsigned int button = BTN_LEFT;
129 	unsigned int trackstick_button = BTN_LEFT;
130 	bool button_mapped = false;
131 	int i;
132 	int button_count = min_t(u8, f3a->gpio_count, TRACKSTICK_RANGE_END);
133 
134 	f3a->gpio_key_map = devm_kcalloc(&fn->dev,
135 						button_count,
136 						sizeof(f3a->gpio_key_map[0]),
137 						GFP_KERNEL);
138 	if (!f3a->gpio_key_map) {
139 		dev_err(&fn->dev, "Failed to allocate gpio map memory.\n");
140 		return -ENOMEM;
141 	}
142 
143 	for (i = 0; i < button_count; i++) {
144 		if (!rmi_f3a_is_valid_button(i, f3a, query1_regs, ctrl1_regs))
145 			continue;
146 
147 		if (pdata->gpio_data.trackstick_buttons &&
148 			i >= TRACKSTICK_RANGE_START &&
149 			i < TRACKSTICK_RANGE_END) {
150 			f3a->gpio_key_map[i] = trackstick_button++;
151 		} else if (!pdata->gpio_data.buttonpad || !button_mapped) {
152 			f3a->gpio_key_map[i] = button;
153 			input_set_capability(input, EV_KEY, button++);
154 			button_mapped = true;
155 		}
156 	}
157 	input->keycode = f3a->gpio_key_map;
158 	input->keycodesize = sizeof(f3a->gpio_key_map[0]);
159 	input->keycodemax = f3a->gpio_count;
160 
161 	if (pdata->gpio_data.buttonpad || (button - BTN_LEFT == 1))
162 		__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
163 
164 	return 0;
165 }
166 
167 static int rmi_f3a_initialize(struct rmi_function *fn, struct f3a_data *f3a)
168 {
169 	u8 query1[RMI_F3A_MAX_REG_SIZE];
170 	u8 ctrl1[RMI_F3A_MAX_REG_SIZE];
171 	u8 buf;
172 	int error;
173 
174 	error = rmi_read(fn->rmi_dev, fn->fd.query_base_addr, &buf);
175 	if (error < 0) {
176 		dev_err(&fn->dev, "Failed to read general info register: %d\n",
177 			error);
178 		return -ENODEV;
179 	}
180 
181 	f3a->gpio_count = buf & RMI_F3A_GPIO_COUNT;
182 	f3a->register_count = DIV_ROUND_UP(f3a->gpio_count, 8);
183 
184 	/* Query1 -> gpio exist */
185 	error = rmi_read_block(fn->rmi_dev, fn->fd.query_base_addr + 1,
186 				query1, f3a->register_count);
187 	if (error) {
188 		dev_err(&fn->dev, "Failed to read query1 register\n");
189 		return error;
190 	}
191 
192 	/* Ctrl1 -> gpio direction */
193 	error = rmi_read_block(fn->rmi_dev, fn->fd.control_base_addr + 1,
194 				ctrl1, f3a->register_count);
195 	if (error) {
196 		dev_err(&fn->dev, "Failed to read control1 register\n");
197 		return error;
198 	}
199 
200 	error = rmi_f3a_map_gpios(fn, f3a, query1, ctrl1);
201 	if (error)
202 		return error;
203 
204 	return 0;
205 }
206 
207 static int rmi_f3a_probe(struct rmi_function *fn)
208 {
209 	struct rmi_device *rmi_dev = fn->rmi_dev;
210 	struct rmi_driver_data *drv_data = dev_get_drvdata(&rmi_dev->dev);
211 	struct f3a_data *f3a;
212 	int error;
213 
214 	if (!drv_data->input) {
215 		dev_info(&fn->dev, "F3A: no input device found, ignoring\n");
216 		return -ENXIO;
217 	}
218 
219 	f3a = devm_kzalloc(&fn->dev, sizeof(*f3a), GFP_KERNEL);
220 	if (!f3a)
221 		return -ENOMEM;
222 
223 	f3a->input = drv_data->input;
224 
225 	error = rmi_f3a_initialize(fn, f3a);
226 	if (error)
227 		return error;
228 
229 	dev_set_drvdata(&fn->dev, f3a);
230 	return 0;
231 }
232 
233 struct rmi_function_handler rmi_f3a_handler = {
234 	.driver = {
235 		.name = "rmi4_f3a",
236 	},
237 	.func = 0x3a,
238 	.probe = rmi_f3a_probe,
239 	.config = rmi_f3a_config,
240 	.attention = rmi_f3a_attention,
241 };
242