1 /*
2  * linux/drivers/misc/xillybus_of.c
3  *
4  * Copyright 2011 Xillybus Ltd, http://xillybus.com
5  *
6  * Driver for the Xillybus FPGA/host framework using Open Firmware.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the smems of the GNU General Public License as published by
10  * the Free Software Foundation; version 2 of the License.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/device.h>
15 #include <linux/slab.h>
16 #include <linux/platform_device.h>
17 #include <linux/of.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_address.h>
20 #include <linux/of_device.h>
21 #include <linux/of_platform.h>
22 #include <linux/err.h>
23 #include "xillybus.h"
24 
25 MODULE_DESCRIPTION("Xillybus driver for Open Firmware");
26 MODULE_AUTHOR("Eli Billauer, Xillybus Ltd.");
27 MODULE_VERSION("1.06");
28 MODULE_ALIAS("xillybus_of");
29 MODULE_LICENSE("GPL v2");
30 
31 static const char xillyname[] = "xillybus_of";
32 
33 /* Match table for of_platform binding */
34 static struct of_device_id xillybus_of_match[] = {
35 	{ .compatible = "xillybus,xillybus-1.00.a", },
36 	{ .compatible = "xlnx,xillybus-1.00.a", }, /* Deprecated */
37 	{}
38 };
39 
40 MODULE_DEVICE_TABLE(of, xillybus_of_match);
41 
42 static void xilly_dma_sync_single_for_cpu_of(struct xilly_endpoint *ep,
43 					     dma_addr_t dma_handle,
44 					     size_t size,
45 					     int direction)
46 {
47 	dma_sync_single_for_cpu(ep->dev, dma_handle, size, direction);
48 }
49 
50 static void xilly_dma_sync_single_for_device_of(struct xilly_endpoint *ep,
51 						dma_addr_t dma_handle,
52 						size_t size,
53 						int direction)
54 {
55 	dma_sync_single_for_device(ep->dev, dma_handle, size, direction);
56 }
57 
58 static void xilly_dma_sync_single_nop(struct xilly_endpoint *ep,
59 				      dma_addr_t dma_handle,
60 				      size_t size,
61 				      int direction)
62 {
63 }
64 
65 static void xilly_of_unmap(void *ptr)
66 {
67 	struct xilly_mapping *data = ptr;
68 
69 	dma_unmap_single(data->device, data->dma_addr,
70 			 data->size, data->direction);
71 
72 	kfree(ptr);
73 }
74 
75 static int xilly_map_single_of(struct xilly_endpoint *ep,
76 			       void *ptr,
77 			       size_t size,
78 			       int direction,
79 			       dma_addr_t *ret_dma_handle
80 	)
81 {
82 	dma_addr_t addr;
83 	struct xilly_mapping *this;
84 	int rc;
85 
86 	this = kzalloc(sizeof(*this), GFP_KERNEL);
87 	if (!this)
88 		return -ENOMEM;
89 
90 	addr = dma_map_single(ep->dev, ptr, size, direction);
91 
92 	if (dma_mapping_error(ep->dev, addr)) {
93 		kfree(this);
94 		return -ENODEV;
95 	}
96 
97 	this->device = ep->dev;
98 	this->dma_addr = addr;
99 	this->size = size;
100 	this->direction = direction;
101 
102 	*ret_dma_handle = addr;
103 
104 	rc = devm_add_action(ep->dev, xilly_of_unmap, this);
105 
106 	if (rc) {
107 		dma_unmap_single(ep->dev, addr, size, direction);
108 		kfree(this);
109 		return rc;
110 	}
111 
112 	return 0;
113 }
114 
115 static struct xilly_endpoint_hardware of_hw = {
116 	.owner = THIS_MODULE,
117 	.hw_sync_sgl_for_cpu = xilly_dma_sync_single_for_cpu_of,
118 	.hw_sync_sgl_for_device = xilly_dma_sync_single_for_device_of,
119 	.map_single = xilly_map_single_of,
120 };
121 
122 static struct xilly_endpoint_hardware of_hw_coherent = {
123 	.owner = THIS_MODULE,
124 	.hw_sync_sgl_for_cpu = xilly_dma_sync_single_nop,
125 	.hw_sync_sgl_for_device = xilly_dma_sync_single_nop,
126 	.map_single = xilly_map_single_of,
127 };
128 
129 static int xilly_drv_probe(struct platform_device *op)
130 {
131 	struct device *dev = &op->dev;
132 	struct xilly_endpoint *endpoint;
133 	int rc;
134 	int irq;
135 	struct resource res;
136 	struct xilly_endpoint_hardware *ephw = &of_hw;
137 
138 	if (of_property_read_bool(dev->of_node, "dma-coherent"))
139 		ephw = &of_hw_coherent;
140 
141 	endpoint = xillybus_init_endpoint(NULL, dev, ephw);
142 
143 	if (!endpoint)
144 		return -ENOMEM;
145 
146 	dev_set_drvdata(dev, endpoint);
147 
148 	rc = of_address_to_resource(dev->of_node, 0, &res);
149 	endpoint->registers = devm_ioremap_resource(dev, &res);
150 
151 	if (IS_ERR(endpoint->registers))
152 		return PTR_ERR(endpoint->registers);
153 
154 	irq = irq_of_parse_and_map(dev->of_node, 0);
155 
156 	rc = devm_request_irq(dev, irq, xillybus_isr, 0, xillyname, endpoint);
157 
158 	if (rc) {
159 		dev_err(endpoint->dev,
160 			"Failed to register IRQ handler. Aborting.\n");
161 		return -ENODEV;
162 	}
163 
164 	return xillybus_endpoint_discovery(endpoint);
165 }
166 
167 static int xilly_drv_remove(struct platform_device *op)
168 {
169 	struct device *dev = &op->dev;
170 	struct xilly_endpoint *endpoint = dev_get_drvdata(dev);
171 
172 	xillybus_endpoint_remove(endpoint);
173 
174 	return 0;
175 }
176 
177 static struct platform_driver xillybus_platform_driver = {
178 	.probe = xilly_drv_probe,
179 	.remove = xilly_drv_remove,
180 	.driver = {
181 		.name = xillyname,
182 		.of_match_table = xillybus_of_match,
183 	},
184 };
185 
186 module_platform_driver(xillybus_platform_driver);
187