xref: /openbmc/linux/drivers/misc/ti-st/st_ll.c (revision feac8c8b)
1 /*
2  *  Shared Transport driver
3  *	HCI-LL module responsible for TI proprietary HCI_LL protocol
4  *  Copyright (C) 2009-2010 Texas Instruments
5  *  Author: Pavan Savoy <pavan_savoy@ti.com>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License version 2 as
9  *  published by the Free Software Foundation.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to the Free Software
18  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
19  *
20  */
21 
22 #define pr_fmt(fmt) "(stll) :" fmt
23 #include <linux/skbuff.h>
24 #include <linux/module.h>
25 #include <linux/platform_device.h>
26 #include <linux/ti_wilink_st.h>
27 
28 /**********************************************************************/
29 /* internal functions */
30 static void send_ll_cmd(struct st_data_s *st_data,
31 	unsigned char cmd)
32 {
33 
34 	pr_debug("%s: writing %x", __func__, cmd);
35 	st_int_write(st_data, &cmd, 1);
36 	return;
37 }
38 
39 static void ll_device_want_to_sleep(struct st_data_s *st_data)
40 {
41 	struct kim_data_s	*kim_data;
42 	struct ti_st_plat_data	*pdata;
43 
44 	pr_debug("%s", __func__);
45 	/* sanity check */
46 	if (st_data->ll_state != ST_LL_AWAKE)
47 		pr_err("ERR hcill: ST_LL_GO_TO_SLEEP_IND"
48 			  "in state %ld", st_data->ll_state);
49 
50 	send_ll_cmd(st_data, LL_SLEEP_ACK);
51 	/* update state */
52 	st_data->ll_state = ST_LL_ASLEEP;
53 
54 	/* communicate to platform about chip asleep */
55 	kim_data = st_data->kim_data;
56 	pdata = kim_data->kim_pdev->dev.platform_data;
57 	if (pdata->chip_asleep)
58 		pdata->chip_asleep(NULL);
59 }
60 
61 static void ll_device_want_to_wakeup(struct st_data_s *st_data)
62 {
63 	struct kim_data_s	*kim_data;
64 	struct ti_st_plat_data	*pdata;
65 
66 	/* diff actions in diff states */
67 	switch (st_data->ll_state) {
68 	case ST_LL_ASLEEP:
69 		send_ll_cmd(st_data, LL_WAKE_UP_ACK);	/* send wake_ack */
70 		break;
71 	case ST_LL_ASLEEP_TO_AWAKE:
72 		/* duplicate wake_ind */
73 		pr_err("duplicate wake_ind while waiting for Wake ack");
74 		break;
75 	case ST_LL_AWAKE:
76 		/* duplicate wake_ind */
77 		pr_err("duplicate wake_ind already AWAKE");
78 		break;
79 	case ST_LL_AWAKE_TO_ASLEEP:
80 		/* duplicate wake_ind */
81 		pr_err("duplicate wake_ind");
82 		break;
83 	}
84 	/* update state */
85 	st_data->ll_state = ST_LL_AWAKE;
86 
87 	/* communicate to platform about chip wakeup */
88 	kim_data = st_data->kim_data;
89 	pdata = kim_data->kim_pdev->dev.platform_data;
90 	if (pdata->chip_awake)
91 		pdata->chip_awake(NULL);
92 }
93 
94 /**********************************************************************/
95 /* functions invoked by ST Core */
96 
97 /* called when ST Core wants to
98  * enable ST LL */
99 void st_ll_enable(struct st_data_s *ll)
100 {
101 	ll->ll_state = ST_LL_AWAKE;
102 }
103 
104 /* called when ST Core /local module wants to
105  * disable ST LL */
106 void st_ll_disable(struct st_data_s *ll)
107 {
108 	ll->ll_state = ST_LL_INVALID;
109 }
110 
111 /* called when ST Core wants to update the state */
112 void st_ll_wakeup(struct st_data_s *ll)
113 {
114 	if (likely(ll->ll_state != ST_LL_AWAKE)) {
115 		send_ll_cmd(ll, LL_WAKE_UP_IND);	/* WAKE_IND */
116 		ll->ll_state = ST_LL_ASLEEP_TO_AWAKE;
117 	} else {
118 		/* don't send the duplicate wake_indication */
119 		pr_err(" Chip already AWAKE ");
120 	}
121 }
122 
123 /* called when ST Core wants the state */
124 unsigned long st_ll_getstate(struct st_data_s *ll)
125 {
126 	pr_debug(" returning state %ld", ll->ll_state);
127 	return ll->ll_state;
128 }
129 
130 /* called from ST Core, when a PM related packet arrives */
131 unsigned long st_ll_sleep_state(struct st_data_s *st_data,
132 	unsigned char cmd)
133 {
134 	switch (cmd) {
135 	case LL_SLEEP_IND:	/* sleep ind */
136 		pr_debug("sleep indication recvd");
137 		ll_device_want_to_sleep(st_data);
138 		break;
139 	case LL_SLEEP_ACK:	/* sleep ack */
140 		pr_err("sleep ack rcvd: host shouldn't");
141 		break;
142 	case LL_WAKE_UP_IND:	/* wake ind */
143 		pr_debug("wake indication recvd");
144 		ll_device_want_to_wakeup(st_data);
145 		break;
146 	case LL_WAKE_UP_ACK:	/* wake ack */
147 		pr_debug("wake ack rcvd");
148 		st_data->ll_state = ST_LL_AWAKE;
149 		break;
150 	default:
151 		pr_err(" unknown input/state ");
152 		return -EINVAL;
153 	}
154 	return 0;
155 }
156 
157 /* Called from ST CORE to initialize ST LL */
158 long st_ll_init(struct st_data_s *ll)
159 {
160 	/* set state to invalid */
161 	ll->ll_state = ST_LL_INVALID;
162 	return 0;
163 }
164 
165 /* Called from ST CORE to de-initialize ST LL */
166 long st_ll_deinit(struct st_data_s *ll)
167 {
168 	return 0;
169 }
170