xref: /linux-6.15/drivers/soundwire/debugfs.c (revision 836c8a2e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 // Copyright(c) 2017-2019 Intel Corporation.
3 
4 #include <linux/cleanup.h>
5 #include <linux/device.h>
6 #include <linux/debugfs.h>
7 #include <linux/firmware.h>
8 #include <linux/mod_devicetable.h>
9 #include <linux/pm_runtime.h>
10 #include <linux/slab.h>
11 #include <linux/soundwire/sdw.h>
12 #include <linux/soundwire/sdw_registers.h>
13 #include <linux/string_choices.h>
14 #include "bus.h"
15 
16 static struct dentry *sdw_debugfs_root;
17 
18 void sdw_bus_debugfs_init(struct sdw_bus *bus)
19 {
20 	char name[16];
21 
22 	if (!sdw_debugfs_root)
23 		return;
24 
25 	/* create the debugfs master-N */
26 	snprintf(name, sizeof(name), "master-%d-%d", bus->controller_id, bus->link_id);
27 	bus->debugfs = debugfs_create_dir(name, sdw_debugfs_root);
28 }
29 
30 void sdw_bus_debugfs_exit(struct sdw_bus *bus)
31 {
32 	debugfs_remove_recursive(bus->debugfs);
33 }
34 
35 #define RD_BUF (3 * PAGE_SIZE)
36 
37 static ssize_t sdw_sprintf(struct sdw_slave *slave,
38 			   char *buf, size_t pos, unsigned int reg)
39 {
40 	int value;
41 
42 	value = sdw_read_no_pm(slave, reg);
43 
44 	if (value < 0)
45 		return scnprintf(buf + pos, RD_BUF - pos, "%3x\tXX\n", reg);
46 	else
47 		return scnprintf(buf + pos, RD_BUF - pos,
48 				"%3x\t%2x\n", reg, value);
49 }
50 
51 static int sdw_slave_reg_show(struct seq_file *s_file, void *data)
52 {
53 	struct sdw_slave *slave = s_file->private;
54 	ssize_t ret;
55 	int i, j;
56 
57 	char *buf __free(kfree) = kzalloc(RD_BUF, GFP_KERNEL);
58 	if (!buf)
59 		return -ENOMEM;
60 
61 	ret = pm_runtime_get_sync(&slave->dev);
62 	if (ret < 0 && ret != -EACCES) {
63 		pm_runtime_put_noidle(&slave->dev);
64 		return ret;
65 	}
66 
67 	ret = scnprintf(buf, RD_BUF, "Register  Value\n");
68 
69 	/* DP0 non-banked registers */
70 	ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP0\n");
71 	for (i = SDW_DP0_INT; i <= SDW_DP0_PREPARECTRL; i++)
72 		ret += sdw_sprintf(slave, buf, ret, i);
73 
74 	/* DP0 Bank 0 registers */
75 	ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n");
76 	ret += sdw_sprintf(slave, buf, ret, SDW_DP0_CHANNELEN);
77 	for (i = SDW_DP0_SAMPLECTRL1; i <= SDW_DP0_LANECTRL; i++)
78 		ret += sdw_sprintf(slave, buf, ret, i);
79 
80 	/* DP0 Bank 1 registers */
81 	ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n");
82 	ret += sdw_sprintf(slave, buf, ret,
83 			SDW_DP0_CHANNELEN + SDW_BANK1_OFFSET);
84 	for (i = SDW_DP0_SAMPLECTRL1 + SDW_BANK1_OFFSET;
85 			i <= SDW_DP0_LANECTRL + SDW_BANK1_OFFSET; i++)
86 		ret += sdw_sprintf(slave, buf, ret, i);
87 
88 	/* SCP registers */
89 	ret += scnprintf(buf + ret, RD_BUF - ret, "\nSCP\n");
90 	for (i = SDW_SCP_INT1; i <= SDW_SCP_BUS_CLOCK_BASE; i++)
91 		ret += sdw_sprintf(slave, buf, ret, i);
92 	for (i = SDW_SCP_DEVID_0; i <= SDW_SCP_DEVID_5; i++)
93 		ret += sdw_sprintf(slave, buf, ret, i);
94 	for (i = SDW_SCP_FRAMECTRL_B0; i <= SDW_SCP_BUSCLOCK_SCALE_B0; i++)
95 		ret += sdw_sprintf(slave, buf, ret, i);
96 	for (i = SDW_SCP_FRAMECTRL_B1; i <= SDW_SCP_BUSCLOCK_SCALE_B1; i++)
97 		ret += sdw_sprintf(slave, buf, ret, i);
98 	for (i = SDW_SCP_PHY_OUT_CTRL_0; i <= SDW_SCP_PHY_OUT_CTRL_7; i++)
99 		ret += sdw_sprintf(slave, buf, ret, i);
100 
101 
102 	/*
103 	 * SCP Bank 0/1 registers are read-only and cannot be
104 	 * retrieved from the Slave. The Master typically keeps track
105 	 * of the current frame size so the information can be found
106 	 * in other places
107 	 */
108 
109 	/* DP1..14 registers */
110 	for (i = 1; SDW_VALID_PORT_RANGE(i); i++) {
111 
112 		/* DPi registers */
113 		ret += scnprintf(buf + ret, RD_BUF - ret, "\nDP%d\n", i);
114 		for (j = SDW_DPN_INT(i); j <= SDW_DPN_PREPARECTRL(i); j++)
115 			ret += sdw_sprintf(slave, buf, ret, j);
116 
117 		/* DPi Bank0 registers */
118 		ret += scnprintf(buf + ret, RD_BUF - ret, "Bank0\n");
119 		for (j = SDW_DPN_CHANNELEN_B0(i);
120 		     j <= SDW_DPN_LANECTRL_B0(i); j++)
121 			ret += sdw_sprintf(slave, buf, ret, j);
122 
123 		/* DPi Bank1 registers */
124 		ret += scnprintf(buf + ret, RD_BUF - ret, "Bank1\n");
125 		for (j = SDW_DPN_CHANNELEN_B1(i);
126 		     j <= SDW_DPN_LANECTRL_B1(i); j++)
127 			ret += sdw_sprintf(slave, buf, ret, j);
128 	}
129 
130 	seq_printf(s_file, "%s", buf);
131 
132 	pm_runtime_mark_last_busy(&slave->dev);
133 	pm_runtime_put(&slave->dev);
134 
135 	return 0;
136 }
137 DEFINE_SHOW_ATTRIBUTE(sdw_slave_reg);
138 
139 #define MAX_CMD_BYTES 256
140 
141 static int cmd;
142 static u32 start_addr;
143 static size_t num_bytes;
144 static u8 read_buffer[MAX_CMD_BYTES];
145 static char *firmware_file;
146 
147 static int set_command(void *data, u64 value)
148 {
149 	struct sdw_slave *slave = data;
150 
151 	if (value > 1)
152 		return -EINVAL;
153 
154 	/* Userspace changed the hardware state behind the kernel's back */
155 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
156 
157 	dev_dbg(&slave->dev, "command: %s\n", str_read_write(value));
158 	cmd = value;
159 
160 	return 0;
161 }
162 DEFINE_DEBUGFS_ATTRIBUTE(set_command_fops, NULL,
163 			 set_command, "%llu\n");
164 
165 static int set_start_address(void *data, u64 value)
166 {
167 	struct sdw_slave *slave = data;
168 
169 	/* Userspace changed the hardware state behind the kernel's back */
170 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
171 
172 	dev_dbg(&slave->dev, "start address %#llx\n", value);
173 
174 	start_addr = value;
175 
176 	return 0;
177 }
178 DEFINE_DEBUGFS_ATTRIBUTE(set_start_address_fops, NULL,
179 			 set_start_address, "%llu\n");
180 
181 static int set_num_bytes(void *data, u64 value)
182 {
183 	struct sdw_slave *slave = data;
184 
185 	if (value == 0 || value > MAX_CMD_BYTES)
186 		return -EINVAL;
187 
188 	/* Userspace changed the hardware state behind the kernel's back */
189 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
190 
191 	dev_dbg(&slave->dev, "number of bytes %lld\n", value);
192 
193 	num_bytes = value;
194 
195 	return 0;
196 }
197 DEFINE_DEBUGFS_ATTRIBUTE(set_num_bytes_fops, NULL,
198 			 set_num_bytes, "%llu\n");
199 
200 static int cmd_go(void *data, u64 value)
201 {
202 	struct sdw_slave *slave = data;
203 	int ret;
204 
205 	if (value != 1)
206 		return -EINVAL;
207 
208 	/* one last check */
209 	if (start_addr > SDW_REG_MAX ||
210 	    num_bytes == 0 || num_bytes > MAX_CMD_BYTES)
211 		return -EINVAL;
212 
213 	ret = pm_runtime_get_sync(&slave->dev);
214 	if (ret < 0 && ret != -EACCES) {
215 		pm_runtime_put_noidle(&slave->dev);
216 		return ret;
217 	}
218 
219 	/* Userspace changed the hardware state behind the kernel's back */
220 	add_taint(TAINT_USER, LOCKDEP_STILL_OK);
221 
222 	dev_dbg(&slave->dev, "starting command\n");
223 
224 	if (cmd == 0) {
225 		const struct firmware *fw;
226 
227 		ret = request_firmware(&fw, firmware_file, &slave->dev);
228 		if (ret < 0) {
229 			dev_err(&slave->dev, "firmware %s not found\n", firmware_file);
230 			goto out;
231 		}
232 
233 		if (fw->size != num_bytes) {
234 			dev_err(&slave->dev,
235 				"firmware %s: unexpected size %zd, desired %zd\n",
236 				firmware_file, fw->size, num_bytes);
237 			release_firmware(fw);
238 			goto out;
239 		}
240 
241 		ret = sdw_nwrite_no_pm(slave, start_addr, num_bytes, fw->data);
242 		release_firmware(fw);
243 	} else {
244 		ret = sdw_nread_no_pm(slave, start_addr, num_bytes, read_buffer);
245 	}
246 
247 	dev_dbg(&slave->dev, "command completed %d\n", ret);
248 
249 out:
250 	pm_runtime_mark_last_busy(&slave->dev);
251 	pm_runtime_put(&slave->dev);
252 
253 	return ret;
254 }
255 DEFINE_DEBUGFS_ATTRIBUTE(cmd_go_fops, NULL,
256 			 cmd_go, "%llu\n");
257 
258 #define MAX_LINE_LEN 128
259 
260 static int read_buffer_show(struct seq_file *s_file, void *data)
261 {
262 	char buf[MAX_LINE_LEN];
263 	int i;
264 
265 	if (num_bytes == 0 || num_bytes > MAX_CMD_BYTES)
266 		return -EINVAL;
267 
268 	for (i = 0; i < num_bytes; i++) {
269 		scnprintf(buf, MAX_LINE_LEN, "address %#x val 0x%02x\n",
270 			  start_addr + i, read_buffer[i]);
271 		seq_printf(s_file, "%s", buf);
272 	}
273 
274 	return 0;
275 }
276 DEFINE_SHOW_ATTRIBUTE(read_buffer);
277 
278 void sdw_slave_debugfs_init(struct sdw_slave *slave)
279 {
280 	struct dentry *master;
281 	struct dentry *d;
282 	char name[32];
283 
284 	master = slave->bus->debugfs;
285 
286 	/* create the debugfs slave-name */
287 	snprintf(name, sizeof(name), "%s", dev_name(&slave->dev));
288 	d = debugfs_create_dir(name, master);
289 
290 	debugfs_create_file("registers", 0400, d, slave, &sdw_slave_reg_fops);
291 
292 	/* interface to send arbitrary commands */
293 	debugfs_create_file("command", 0200, d, slave, &set_command_fops);
294 	debugfs_create_file("start_address", 0200, d, slave, &set_start_address_fops);
295 	debugfs_create_file("num_bytes", 0200, d, slave, &set_num_bytes_fops);
296 	debugfs_create_file("go", 0200, d, slave, &cmd_go_fops);
297 
298 	debugfs_create_file("read_buffer", 0400, d, slave, &read_buffer_fops);
299 	firmware_file = NULL;
300 	debugfs_create_str("firmware_file", 0200, d, &firmware_file);
301 
302 	slave->debugfs = d;
303 }
304 
305 void sdw_slave_debugfs_exit(struct sdw_slave *slave)
306 {
307 	debugfs_remove_recursive(slave->debugfs);
308 }
309 
310 void sdw_debugfs_init(void)
311 {
312 	sdw_debugfs_root = debugfs_create_dir("soundwire", NULL);
313 }
314 
315 void sdw_debugfs_exit(void)
316 {
317 	debugfs_remove_recursive(sdw_debugfs_root);
318 }
319