1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
|
From ff3d8063eed907bed728a14e1519dc659036315a Mon Sep 17 00:00:00 2001
From: Fugang Duan <fugang.duan@nxp.com>
Date: Wed, 11 Sep 2019 16:36:48 +0800
Subject: [PATCH] MLK-17133-02 tty: serial: lpuart: add runtime pm support
Add runtime pm support to manage lpuart clock and its power domain
to save power in system idle and system suspend stages.
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Reviewed-by: Robin Gong <yibin.gong@nxp.com>
---
drivers/tty/serial/fsl_lpuart.c | 80 ++++++++++++++++++++++++++++++++++++-----
1 file changed, 72 insertions(+), 8 deletions(-)
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -245,6 +245,7 @@
/* Rx DMA timeout in ms, which is used to calculate Rx ring buffer size */
#define DMA_RX_TIMEOUT (10)
+#define UART_AUTOSUSPEND_TIMEOUT 3000
#define DRIVER_NAME "fsl-lpuart"
#define DEV_NAME "ttyLP"
@@ -859,6 +860,20 @@ static void lpuart32_start_tx(struct uar
}
}
+static void
+lpuart_uart_pm(struct uart_port *port, unsigned int state, unsigned int oldstate)
+{
+ switch (state) {
+ case UART_PM_STATE_OFF:
+ pm_runtime_mark_last_busy(port->dev);
+ pm_runtime_put_autosuspend(port->dev);
+ break;
+ default:
+ pm_runtime_get_sync(port->dev);
+ break;
+ }
+}
+
/* return TIOCSER_TEMT when transmitter is not busy */
static unsigned int lpuart_tx_empty(struct uart_port *port)
{
@@ -2283,6 +2298,7 @@ static const struct uart_ops lpuart_pops
.break_ctl = lpuart_break_ctl,
.startup = lpuart_startup,
.shutdown = lpuart_shutdown,
+ .pm = lpuart_uart_pm,
.set_termios = lpuart_set_termios,
.type = lpuart_type,
.request_port = lpuart_request_port,
@@ -2307,6 +2323,7 @@ static const struct uart_ops lpuart32_po
.break_ctl = lpuart32_break_ctl,
.startup = lpuart32_startup,
.shutdown = lpuart32_shutdown,
+ .pm = lpuart_uart_pm,
.set_termios = lpuart32_set_termios,
.type = lpuart_type,
.request_port = lpuart_request_port,
@@ -2766,6 +2783,11 @@ static int lpuart_probe(struct platform_
if (ret)
goto failed_irq_request;
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
ret = uart_add_one_port(&lpuart_reg, &sport->port);
if (ret)
goto failed_attach_port;
@@ -2800,6 +2822,9 @@ static int lpuart_probe(struct platform_
failed_reset:
uart_remove_one_port(&lpuart_reg, &sport->port);
failed_attach_port:
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
failed_irq_request:
lpuart_disable_clks(sport);
failed_clock_enable:
@@ -2826,15 +2851,41 @@ static int lpuart_remove(struct platform
if (sport->dma_rx_chan)
dma_release_channel(sport->dma_rx_chan);
+ pm_runtime_disable(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
return 0;
}
#ifdef CONFIG_PM_SLEEP
+static int lpuart_runtime_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct lpuart_port *sport = platform_get_drvdata(pdev);
+
+ lpuart_disable_clks(sport);
+
+ return 0;
+};
+
+static int lpuart_runtime_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct lpuart_port *sport = platform_get_drvdata(pdev);
+
+ return lpuart_enable_clks(sport);
+};
+
static int lpuart_suspend(struct device *dev)
{
struct lpuart_port *sport = dev_get_drvdata(dev);
unsigned long temp;
bool irq_wake;
+ int ret;
+
+ ret = clk_prepare_enable(sport->ipg_clk);
+ if (ret)
+ return ret;
if (lpuart_is_32(sport)) {
/* disable Rx/Tx and interrupts */
@@ -2848,10 +2899,14 @@ static int lpuart_suspend(struct device
writeb(temp, sport->port.membase + UARTCR2);
}
+ clk_disable_unprepare(sport->ipg_clk);
+
uart_suspend_port(&lpuart_reg, &sport->port);
/* uart_suspend_port() might set wakeup flag */
irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
+ if (sport->port.suspended && !irq_wake)
+ return 0;
if (sport->lpuart_dma_rx_use) {
/*
@@ -2882,9 +2937,6 @@ static int lpuart_suspend(struct device
dmaengine_terminate_all(sport->dma_tx_chan);
}
- if (sport->port.suspended && !irq_wake)
- lpuart_disable_clks(sport);
-
return 0;
}
@@ -2892,9 +2944,11 @@ static int lpuart_resume(struct device *
{
struct lpuart_port *sport = dev_get_drvdata(dev);
bool irq_wake = irqd_is_wakeup_set(irq_get_irq_data(sport->port.irq));
+ int ret;
- if (sport->port.suspended && !irq_wake)
- lpuart_enable_clks(sport);
+ ret = clk_prepare_enable(sport->ipg_clk);
+ if (ret)
+ return ret;
if (lpuart_is_32(sport))
lpuart32_setup_watermark_enable(sport);
@@ -2915,13 +2969,23 @@ static int lpuart_resume(struct device *
if (lpuart_is_32(sport))
lpuart32_configure(sport);
+ clk_disable_unprepare(sport->ipg_clk);
+
uart_resume_port(&lpuart_reg, &sport->port);
return 0;
}
-#endif
+static const struct dev_pm_ops lpuart_pm_ops = {
+ SET_RUNTIME_PM_OPS(lpuart_runtime_suspend,
+ lpuart_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(lpuart_suspend, lpuart_resume)
+};
+#define SERIAL_LPUART_PM_OPS (&lpuart_pm_ops)
-static SIMPLE_DEV_PM_OPS(lpuart_pm_ops, lpuart_suspend, lpuart_resume);
+#else /* !CONFIG_PM_SLEEP */
+
+#define SERIAL_LPUART_PM_OPS NULL
+#endif
static struct platform_driver lpuart_driver = {
.probe = lpuart_probe,
@@ -2929,7 +2993,7 @@ static struct platform_driver lpuart_dri
.driver = {
.name = "fsl-lpuart",
.of_match_table = lpuart_dt_ids,
- .pm = &lpuart_pm_ops,
+ .pm = SERIAL_LPUART_PM_OPS,
},
};
|
