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
|
From fdbad6304ebb24af8e2b08aa61cb640386cd21ca Mon Sep 17 00:00:00 2001
From: Martin Sperl <kernel@martin.sperl.org>
Date: Tue, 26 Apr 2016 14:59:21 +0000
Subject: [PATCH 050/782] MISC: bcm2835: smi: use clock manager and fix reload
issues
Use clock manager instead of self-made clockmanager.
Also fix some error paths that showd up during development
(especially missing release of dma resources on rmmod)
Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
---
drivers/misc/bcm2835_smi.c | 86 +++++++++++++-------------------------
1 file changed, 28 insertions(+), 58 deletions(-)
--- a/drivers/misc/bcm2835_smi.c
+++ b/drivers/misc/bcm2835_smi.c
@@ -34,6 +34,7 @@
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
+#include <linux/clk.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
@@ -62,7 +63,7 @@
struct bcm2835_smi_instance {
struct device *dev;
struct smi_settings settings;
- __iomem void *smi_regs_ptr, *cm_smi_regs_ptr;
+ __iomem void *smi_regs_ptr;
dma_addr_t smi_regs_busaddr;
struct dma_chan *dma_chan;
@@ -72,8 +73,7 @@ struct bcm2835_smi_instance {
struct scatterlist buffer_sgl;
- int clock_source;
- int clock_divisor;
+ struct clk *clk;
/* Sometimes we are called into in an atomic context (e.g. by
JFFS2 + MTD) so we can't use a mutex */
@@ -82,42 +82,6 @@ struct bcm2835_smi_instance {
/****************************************************************************
*
-* SMI clock manager setup
-*
-***************************************************************************/
-
-static inline void write_smi_cm_reg(struct bcm2835_smi_instance *inst,
- u32 val, unsigned reg)
-{
- writel(CM_PWD | val, inst->cm_smi_regs_ptr + reg);
-}
-
-static inline u32 read_smi_cm_reg(struct bcm2835_smi_instance *inst,
- unsigned reg)
-{
- return readl(inst->cm_smi_regs_ptr + reg);
-}
-
-static void smi_setup_clock(struct bcm2835_smi_instance *inst)
-{
- dev_dbg(inst->dev, "Setting up clock...");
- /* Disable SMI clock and wait for it to stop. */
- write_smi_cm_reg(inst, 0, CM_SMI_CTL);
- while (read_smi_cm_reg(inst, CM_SMI_CTL) & CM_SMI_CTL_BUSY)
- ;
-
- write_smi_cm_reg(inst, (inst->clock_divisor << CM_SMI_DIV_DIVI_OFFS),
- CM_SMI_DIV);
- write_smi_cm_reg(inst, (inst->clock_source << CM_SMI_CTL_SRC_OFFS),
- CM_SMI_CTL);
-
- /* Enable the clock */
- write_smi_cm_reg(inst, (inst->clock_source << CM_SMI_CTL_SRC_OFFS) |
- CM_SMI_CTL_ENAB, CM_SMI_CTL);
-}
-
-/****************************************************************************
-*
* SMI peripheral setup
*
***************************************************************************/
@@ -894,42 +858,40 @@ static int bcm2835_smi_probe(struct plat
struct device_node *node = dev->of_node;
struct resource *ioresource;
struct bcm2835_smi_instance *inst;
+ const __be32 *addr;
+ /* We require device tree support */
+ if (!node)
+ return -EINVAL;
/* Allocate buffers and instance data */
-
inst = devm_kzalloc(dev, sizeof(struct bcm2835_smi_instance),
GFP_KERNEL);
-
if (!inst)
return -ENOMEM;
inst->dev = dev;
spin_lock_init(&inst->transaction_lock);
- /* We require device tree support */
- if (!node)
- return -EINVAL;
-
ioresource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
inst->smi_regs_ptr = devm_ioremap_resource(dev, ioresource);
- ioresource = platform_get_resource(pdev, IORESOURCE_MEM, 1);
- inst->cm_smi_regs_ptr = devm_ioremap_resource(dev, ioresource);
- inst->smi_regs_busaddr = be32_to_cpu(
- *of_get_address(node, 0, NULL, NULL));
- of_property_read_u32(node,
- "brcm,smi-clock-source",
- &inst->clock_source);
- of_property_read_u32(node,
- "brcm,smi-clock-divisor",
- &inst->clock_divisor);
+ if (IS_ERR(inst->smi_regs_ptr)) {
+ err = PTR_ERR(inst->smi_regs_ptr);
+ goto err;
+ }
+ addr = of_get_address(node, 0, NULL, NULL);
+ inst->smi_regs_busaddr = be32_to_cpu(addr);
err = bcm2835_smi_dma_setup(inst);
if (err)
- return err;
+ goto err;
- /* Finally, do peripheral setup */
+ /* request clock */
+ inst->clk = devm_clk_get(dev, NULL);
+ if (!inst->clk)
+ goto err;
+ clk_prepare_enable(inst->clk);
- smi_setup_clock(inst);
+ /* Finally, do peripheral setup */
smi_setup_regs(inst);
platform_set_drvdata(pdev, inst);
@@ -937,6 +899,9 @@ static int bcm2835_smi_probe(struct plat
dev_info(inst->dev, "initialised");
return 0;
+err:
+ kfree(inst);
+ return err;
}
/****************************************************************************
@@ -950,6 +915,11 @@ static int bcm2835_smi_remove(struct pla
struct bcm2835_smi_instance *inst = platform_get_drvdata(pdev);
struct device *dev = inst->dev;
+ dmaengine_terminate_all(inst->dma_chan);
+ dma_release_channel(inst->dma_chan);
+
+ clk_disable_unprepare(inst->clk);
+
dev_info(dev, "SMI device removed - OK");
return 0;
}
|
