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stmmac_timer.c
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1 /*******************************************************************************
2  STMMAC external timer support.
3 
4  Copyright (C) 2007-2009 STMicroelectronics Ltd
5 
6  This program is free software; you can redistribute it and/or modify it
7  under the terms and conditions of the GNU General Public License,
8  version 2, as published by the Free Software Foundation.
9 
10  This program is distributed in the hope it will be useful, but WITHOUT
11  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13  more details.
14 
15  You should have received a copy of the GNU General Public License along with
16  this program; if not, write to the Free Software Foundation, Inc.,
17  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 
19  The full GNU General Public License is included in this distribution in
20  the file called "COPYING".
21 
22  Author: Giuseppe Cavallaro <[email protected]>
23 *******************************************************************************/
24 
25 #include <linux/kernel.h>
26 #include <linux/etherdevice.h>
27 #include "stmmac_timer.h"
28 
29 static void stmmac_timer_handler(void *data)
30 {
31  struct net_device *dev = (struct net_device *)data;
32 
33  stmmac_schedule(dev);
34 }
35 
36 #define STMMAC_TIMER_MSG(timer, freq) \
37 printk(KERN_INFO "stmmac_timer: %s Timer ON (freq %dHz)\n", timer, freq);
38 
39 #if defined(CONFIG_STMMAC_RTC_TIMER)
40 #include <linux/rtc.h>
41 static struct rtc_device *stmmac_rtc;
42 static rtc_task_t stmmac_task;
43 
44 static void stmmac_rtc_start(unsigned int new_freq)
45 {
46  rtc_irq_set_freq(stmmac_rtc, &stmmac_task, new_freq);
47  rtc_irq_set_state(stmmac_rtc, &stmmac_task, 1);
48 }
49 
50 static void stmmac_rtc_stop(void)
51 {
52  rtc_irq_set_state(stmmac_rtc, &stmmac_task, 0);
53 }
54 
56 {
57  stmmac_task.private_data = dev;
58  stmmac_task.func = stmmac_timer_handler;
59 
60  stmmac_rtc = rtc_class_open(CONFIG_RTC_HCTOSYS_DEVICE);
61  if (stmmac_rtc == NULL) {
62  pr_err("open rtc device failed\n");
63  return -ENODEV;
64  }
65 
66  rtc_irq_register(stmmac_rtc, &stmmac_task);
67 
68  /* Periodic mode is not supported */
69  if ((rtc_irq_set_freq(stmmac_rtc, &stmmac_task, tm->freq) < 0)) {
70  pr_err("set periodic failed\n");
71  rtc_irq_unregister(stmmac_rtc, &stmmac_task);
72  rtc_class_close(stmmac_rtc);
73  return -1;
74  }
75 
76  STMMAC_TIMER_MSG(CONFIG_RTC_HCTOSYS_DEVICE, tm->freq);
77 
78  tm->timer_start = stmmac_rtc_start;
79  tm->timer_stop = stmmac_rtc_stop;
80 
81  return 0;
82 }
83 
84 int stmmac_close_ext_timer(void)
85 {
86  rtc_irq_set_state(stmmac_rtc, &stmmac_task, 0);
87  rtc_irq_unregister(stmmac_rtc, &stmmac_task);
88  rtc_class_close(stmmac_rtc);
89  return 0;
90 }
91 
92 #elif defined(CONFIG_STMMAC_TMU_TIMER)
93 #include <linux/clk.h>
94 #define TMU_CHANNEL "tmu2_clk"
95 static struct clk *timer_clock;
96 
97 static void stmmac_tmu_start(unsigned int new_freq)
98 {
99  clk_set_rate(timer_clock, new_freq);
100  clk_prepare_enable(timer_clock);
101 }
102 
103 static void stmmac_tmu_stop(void)
104 {
105  clk_disable_unprepare(timer_clock);
106 }
107 
108 int stmmac_open_ext_timer(struct net_device *dev, struct stmmac_timer *tm)
109 {
110  timer_clock = clk_get(NULL, TMU_CHANNEL);
111 
112  if (IS_ERR(timer_clock))
113  return -1;
114 
115  if (tmu2_register_user(stmmac_timer_handler, (void *)dev) < 0) {
116  timer_clock = NULL;
117  return -1;
118  }
119 
120  STMMAC_TIMER_MSG("TMU2", tm->freq);
121  tm->timer_start = stmmac_tmu_start;
122  tm->timer_stop = stmmac_tmu_stop;
123 
124  return 0;
125 }
126 
127 int stmmac_close_ext_timer(void)
128 {
129  clk_disable_unprepare(timer_clock);
130  tmu2_unregister_user();
131  clk_put(timer_clock);
132  return 0;
133 }
134 #endif