xref: /openbmc/linux/drivers/misc/ti-st/st_ll.c (revision d9fd5a71)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Shared Transport driver
4  *	HCI-LL module responsible for TI proprietary HCI_LL protocol
5  *  Copyright (C) 2009-2010 Texas Instruments
6  *  Author: Pavan Savoy <pavan_savoy@ti.com>
7  */
8 
9 #define pr_fmt(fmt) "(stll) :" fmt
10 #include <linux/skbuff.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/ti_wilink_st.h>
14 
15 /**********************************************************************/
16 /* internal functions */
17 static void send_ll_cmd(struct st_data_s *st_data,
18 	unsigned char cmd)
19 {
20 
21 	pr_debug("%s: writing %x", __func__, cmd);
22 	st_int_write(st_data, &cmd, 1);
23 	return;
24 }
25 
26 static void ll_device_want_to_sleep(struct st_data_s *st_data)
27 {
28 	struct kim_data_s	*kim_data;
29 	struct ti_st_plat_data	*pdata;
30 
31 	pr_debug("%s", __func__);
32 	/* sanity check */
33 	if (st_data->ll_state != ST_LL_AWAKE)
34 		pr_err("ERR hcill: ST_LL_GO_TO_SLEEP_IND"
35 			  "in state %ld", st_data->ll_state);
36 
37 	send_ll_cmd(st_data, LL_SLEEP_ACK);
38 	/* update state */
39 	st_data->ll_state = ST_LL_ASLEEP;
40 
41 	/* communicate to platform about chip asleep */
42 	kim_data = st_data->kim_data;
43 	pdata = kim_data->kim_pdev->dev.platform_data;
44 	if (pdata->chip_asleep)
45 		pdata->chip_asleep(NULL);
46 }
47 
48 static void ll_device_want_to_wakeup(struct st_data_s *st_data)
49 {
50 	struct kim_data_s	*kim_data;
51 	struct ti_st_plat_data	*pdata;
52 
53 	/* diff actions in diff states */
54 	switch (st_data->ll_state) {
55 	case ST_LL_ASLEEP:
56 		send_ll_cmd(st_data, LL_WAKE_UP_ACK);	/* send wake_ack */
57 		break;
58 	case ST_LL_ASLEEP_TO_AWAKE:
59 		/* duplicate wake_ind */
60 		pr_err("duplicate wake_ind while waiting for Wake ack");
61 		break;
62 	case ST_LL_AWAKE:
63 		/* duplicate wake_ind */
64 		pr_err("duplicate wake_ind already AWAKE");
65 		break;
66 	case ST_LL_AWAKE_TO_ASLEEP:
67 		/* duplicate wake_ind */
68 		pr_err("duplicate wake_ind");
69 		break;
70 	}
71 	/* update state */
72 	st_data->ll_state = ST_LL_AWAKE;
73 
74 	/* communicate to platform about chip wakeup */
75 	kim_data = st_data->kim_data;
76 	pdata = kim_data->kim_pdev->dev.platform_data;
77 	if (pdata->chip_awake)
78 		pdata->chip_awake(NULL);
79 }
80 
81 /**********************************************************************/
82 /* functions invoked by ST Core */
83 
84 /* called when ST Core wants to
85  * enable ST LL */
86 void st_ll_enable(struct st_data_s *ll)
87 {
88 	ll->ll_state = ST_LL_AWAKE;
89 }
90 
91 /* called when ST Core /local module wants to
92  * disable ST LL */
93 void st_ll_disable(struct st_data_s *ll)
94 {
95 	ll->ll_state = ST_LL_INVALID;
96 }
97 
98 /* called when ST Core wants to update the state */
99 void st_ll_wakeup(struct st_data_s *ll)
100 {
101 	if (likely(ll->ll_state != ST_LL_AWAKE)) {
102 		send_ll_cmd(ll, LL_WAKE_UP_IND);	/* WAKE_IND */
103 		ll->ll_state = ST_LL_ASLEEP_TO_AWAKE;
104 	} else {
105 		/* don't send the duplicate wake_indication */
106 		pr_err(" Chip already AWAKE ");
107 	}
108 }
109 
110 /* called when ST Core wants the state */
111 unsigned long st_ll_getstate(struct st_data_s *ll)
112 {
113 	pr_debug(" returning state %ld", ll->ll_state);
114 	return ll->ll_state;
115 }
116 
117 /* called from ST Core, when a PM related packet arrives */
118 unsigned long st_ll_sleep_state(struct st_data_s *st_data,
119 	unsigned char cmd)
120 {
121 	switch (cmd) {
122 	case LL_SLEEP_IND:	/* sleep ind */
123 		pr_debug("sleep indication recvd");
124 		ll_device_want_to_sleep(st_data);
125 		break;
126 	case LL_SLEEP_ACK:	/* sleep ack */
127 		pr_err("sleep ack rcvd: host shouldn't");
128 		break;
129 	case LL_WAKE_UP_IND:	/* wake ind */
130 		pr_debug("wake indication recvd");
131 		ll_device_want_to_wakeup(st_data);
132 		break;
133 	case LL_WAKE_UP_ACK:	/* wake ack */
134 		pr_debug("wake ack rcvd");
135 		st_data->ll_state = ST_LL_AWAKE;
136 		break;
137 	default:
138 		pr_err(" unknown input/state ");
139 		return -EINVAL;
140 	}
141 	return 0;
142 }
143 
144 /* Called from ST CORE to initialize ST LL */
145 long st_ll_init(struct st_data_s *ll)
146 {
147 	/* set state to invalid */
148 	ll->ll_state = ST_LL_INVALID;
149 	return 0;
150 }
151 
152 /* Called from ST CORE to de-initialize ST LL */
153 long st_ll_deinit(struct st_data_s *ll)
154 {
155 	return 0;
156 }
157