1// SPDX-License-Identifier: GPL-2.0
2#include <linux/libata.h>
3#include <linux/cdrom.h>
4#include <linux/pm_runtime.h>
5#include <linux/module.h>
6#include <linux/pm_qos.h>
7#include <scsi/scsi_device.h>
8
9#include "libata.h"
10
11static int zpodd_poweroff_delay = 30; /* 30 seconds for power off delay */
12module_param(zpodd_poweroff_delay, int, 0644);
13MODULE_PARM_DESC(zpodd_poweroff_delay, "Poweroff delay for ZPODD in seconds");
14
15enum odd_mech_type {
16	ODD_MECH_TYPE_SLOT,
17	ODD_MECH_TYPE_DRAWER,
18	ODD_MECH_TYPE_UNSUPPORTED,
19};
20
21struct zpodd {
22	enum odd_mech_type	mech_type; /* init during probe, RO afterwards */
23	struct ata_device	*dev;
24
25	/* The following fields are synchronized by PM core. */
26	bool			from_notify; /* resumed as a result of
27					      * acpi wake notification */
28	bool			zp_ready; /* ZP ready state */
29	unsigned long		last_ready; /* last ZP ready timestamp */
30	bool			zp_sampled; /* ZP ready state sampled */
31	bool			powered_off; /* ODD is powered off
32					      *	during suspend */
33};
34
35static int eject_tray(struct ata_device *dev)
36{
37	struct ata_taskfile tf;
38	static const char cdb[ATAPI_CDB_LEN] = {  GPCMD_START_STOP_UNIT,
39		0, 0, 0,
40		0x02,     /* LoEj */
41		0, 0, 0, 0, 0, 0, 0,
42	};
43
44	ata_tf_init(dev, &tf);
45	tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
46	tf.command = ATA_CMD_PACKET;
47	tf.protocol = ATAPI_PROT_NODATA;
48
49	return ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
50}
51
52/* Per the spec, only slot type and drawer type ODD can be supported */
53static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
54{
55	char *buf;
56	unsigned int ret;
57	struct rm_feature_desc *desc;
58	struct ata_taskfile tf;
59	static const char cdb[ATAPI_CDB_LEN] = {  GPCMD_GET_CONFIGURATION,
60			2,      /* only 1 feature descriptor requested */
61			0, 3,   /* 3, removable medium feature */
62			0, 0, 0,/* reserved */
63			0, 16,
64			0, 0, 0,
65	};
66
67	buf = kzalloc(16, GFP_KERNEL);
68	if (!buf)
69		return ODD_MECH_TYPE_UNSUPPORTED;
70	desc = (void *)(buf + 8);
71
72	ata_tf_init(dev, &tf);
73	tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
74	tf.command = ATA_CMD_PACKET;
75	tf.protocol = ATAPI_PROT_PIO;
76	tf.lbam = 16;
77
78	ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
79				buf, 16, 0);
80	if (ret) {
81		kfree(buf);
82		return ODD_MECH_TYPE_UNSUPPORTED;
83	}
84
85	if (be16_to_cpu(desc->feature_code) != 3) {
86		kfree(buf);
87		return ODD_MECH_TYPE_UNSUPPORTED;
88	}
89
90	if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1) {
91		kfree(buf);
92		return ODD_MECH_TYPE_SLOT;
93	} else if (desc->mech_type == 1 && desc->load == 0 &&
94		   desc->eject == 1) {
95		kfree(buf);
96		return ODD_MECH_TYPE_DRAWER;
97	} else {
98		kfree(buf);
99		return ODD_MECH_TYPE_UNSUPPORTED;
100	}
101}
102
103/* Test if ODD is zero power ready by sense code */
104static bool zpready(struct ata_device *dev)
105{
106	u8 sense_key, *sense_buf;
107	unsigned int ret, asc, ascq, add_len;
108	struct zpodd *zpodd = dev->zpodd;
109
110	ret = atapi_eh_tur(dev, &sense_key);
111
112	if (!ret || sense_key != NOT_READY)
113		return false;
114
115	sense_buf = dev->link->ap->sector_buf;
116	ret = atapi_eh_request_sense(dev, sense_buf, sense_key);
117	if (ret)
118		return false;
119
120	/* sense valid */
121	if ((sense_buf[0] & 0x7f) != 0x70)
122		return false;
123
124	add_len = sense_buf[7];
125	/* has asc and ascq */
126	if (add_len < 6)
127		return false;
128
129	asc = sense_buf[12];
130	ascq = sense_buf[13];
131
132	if (zpodd->mech_type == ODD_MECH_TYPE_SLOT)
133		/* no media inside */
134		return asc == 0x3a;
135	else
136		/* no media inside and door closed */
137		return asc == 0x3a && ascq == 0x01;
138}
139
140/*
141 * Update the zpodd->zp_ready field. This field will only be set
142 * if the ODD has stayed in ZP ready state for zpodd_poweroff_delay
143 * time, and will be used to decide if power off is allowed. If it
144 * is set, it will be cleared during resume from powered off state.
145 */
146void zpodd_on_suspend(struct ata_device *dev)
147{
148	struct zpodd *zpodd = dev->zpodd;
149	unsigned long expires;
150
151	if (!zpready(dev)) {
152		zpodd->zp_sampled = false;
153		zpodd->zp_ready = false;
154		return;
155	}
156
157	if (!zpodd->zp_sampled) {
158		zpodd->zp_sampled = true;
159		zpodd->last_ready = jiffies;
160		return;
161	}
162
163	expires = zpodd->last_ready +
164		  msecs_to_jiffies(zpodd_poweroff_delay * 1000);
165	if (time_before(jiffies, expires))
166		return;
167
168	zpodd->zp_ready = true;
169}
170
171bool zpodd_zpready(struct ata_device *dev)
172{
173	struct zpodd *zpodd = dev->zpodd;
174	return zpodd->zp_ready;
175}
176
177/*
178 * Enable runtime wake capability through ACPI and set the powered_off flag,
179 * this flag will be used during resume to decide what operations are needed
180 * to take.
181 *
182 * Also, media poll needs to be silenced, so that it doesn't bring the ODD
183 * back to full power state every few seconds.
184 */
185void zpodd_enable_run_wake(struct ata_device *dev)
186{
187	struct zpodd *zpodd = dev->zpodd;
188
189	sdev_disable_disk_events(dev->sdev);
190
191	zpodd->powered_off = true;
192	acpi_pm_set_device_wakeup(&dev->tdev, true);
193}
194
195/* Disable runtime wake capability if it is enabled */
196void zpodd_disable_run_wake(struct ata_device *dev)
197{
198	struct zpodd *zpodd = dev->zpodd;
199
200	if (zpodd->powered_off)
201		acpi_pm_set_device_wakeup(&dev->tdev, false);
202}
203
204/*
205 * Post power on processing after the ODD has been recovered. If the
206 * ODD wasn't powered off during suspend, it doesn't do anything.
207 *
208 * For drawer type ODD, if it is powered on due to user pressed the
209 * eject button, the tray needs to be ejected. This can only be done
210 * after the ODD has been recovered, i.e. link is initialized and
211 * device is able to process NON_DATA PIO command, as eject needs to
212 * send command for the ODD to process.
213 *
214 * The from_notify flag set in wake notification handler function
215 * zpodd_wake_dev represents if power on is due to user's action.
216 *
217 * For both types of ODD, several fields need to be reset.
218 */
219void zpodd_post_poweron(struct ata_device *dev)
220{
221	struct zpodd *zpodd = dev->zpodd;
222
223	if (!zpodd->powered_off)
224		return;
225
226	zpodd->powered_off = false;
227
228	if (zpodd->from_notify) {
229		zpodd->from_notify = false;
230		if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
231			eject_tray(dev);
232	}
233
234	zpodd->zp_sampled = false;
235	zpodd->zp_ready = false;
236
237	sdev_enable_disk_events(dev->sdev);
238}
239
240static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
241{
242	struct ata_device *ata_dev = context;
243	struct zpodd *zpodd = ata_dev->zpodd;
244	struct device *dev = &ata_dev->sdev->sdev_gendev;
245
246	if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
247		zpodd->from_notify = true;
248		pm_runtime_resume(dev);
249	}
250}
251
252static void ata_acpi_add_pm_notifier(struct ata_device *dev)
253{
254	acpi_handle handle = ata_dev_acpi_handle(dev);
255	acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
256				    zpodd_wake_dev, dev);
257}
258
259static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
260{
261	acpi_handle handle = ata_dev_acpi_handle(dev);
262	acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
263}
264
265void zpodd_init(struct ata_device *dev)
266{
267	struct acpi_device *adev = ACPI_COMPANION(&dev->tdev);
268	enum odd_mech_type mech_type;
269	struct zpodd *zpodd;
270
271	if (dev->zpodd || !adev || !acpi_device_can_poweroff(adev))
272		return;
273
274	mech_type = zpodd_get_mech_type(dev);
275	if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
276		return;
277
278	zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
279	if (!zpodd)
280		return;
281
282	zpodd->mech_type = mech_type;
283
284	ata_acpi_add_pm_notifier(dev);
285	zpodd->dev = dev;
286	dev->zpodd = zpodd;
287	dev_pm_qos_expose_flags(&dev->tdev, 0);
288}
289
290void zpodd_exit(struct ata_device *dev)
291{
292	ata_acpi_remove_pm_notifier(dev);
293	kfree(dev->zpodd);
294	dev->zpodd = NULL;
295}
296