Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
[linux-2.6.git] / drivers / spi / spi-fsl-lib.c
1 /*
2  * Freescale SPI/eSPI controller driver library.
3  *
4  * Maintainer: Kumar Gala
5  *
6  * Copyright (C) 2006 Polycom, Inc.
7  *
8  * CPM SPI and QE buffer descriptors mode support:
9  * Copyright (c) 2009  MontaVista Software, Inc.
10  * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
11  *
12  * Copyright 2010 Freescale Semiconductor, Inc.
13  *
14  * This program is free software; you can redistribute  it and/or modify it
15  * under  the terms of  the GNU General  Public License as published by the
16  * Free Software Foundation;  either version 2 of the  License, or (at your
17  * option) any later version.
18  */
19 #include <linux/kernel.h>
20 #include <linux/interrupt.h>
21 #include <linux/fsl_devices.h>
22 #include <linux/dma-mapping.h>
23 #include <linux/mm.h>
24 #include <linux/of_platform.h>
25 #include <linux/of_spi.h>
26 #include <sysdev/fsl_soc.h>
27
28 #include "spi-fsl-lib.h"
29
30 #define MPC8XXX_SPI_RX_BUF(type)                                          \
31 void mpc8xxx_spi_rx_buf_##type(u32 data, struct mpc8xxx_spi *mpc8xxx_spi) \
32 {                                                                         \
33         type *rx = mpc8xxx_spi->rx;                                       \
34         *rx++ = (type)(data >> mpc8xxx_spi->rx_shift);                    \
35         mpc8xxx_spi->rx = rx;                                             \
36 }
37
38 #define MPC8XXX_SPI_TX_BUF(type)                                \
39 u32 mpc8xxx_spi_tx_buf_##type(struct mpc8xxx_spi *mpc8xxx_spi)  \
40 {                                                               \
41         u32 data;                                               \
42         const type *tx = mpc8xxx_spi->tx;                       \
43         if (!tx)                                                \
44                 return 0;                                       \
45         data = *tx++ << mpc8xxx_spi->tx_shift;                  \
46         mpc8xxx_spi->tx = tx;                                   \
47         return data;                                            \
48 }
49
50 MPC8XXX_SPI_RX_BUF(u8)
51 MPC8XXX_SPI_RX_BUF(u16)
52 MPC8XXX_SPI_RX_BUF(u32)
53 MPC8XXX_SPI_TX_BUF(u8)
54 MPC8XXX_SPI_TX_BUF(u16)
55 MPC8XXX_SPI_TX_BUF(u32)
56
57 struct mpc8xxx_spi_probe_info *to_of_pinfo(struct fsl_spi_platform_data *pdata)
58 {
59         return container_of(pdata, struct mpc8xxx_spi_probe_info, pdata);
60 }
61
62 void mpc8xxx_spi_work(struct work_struct *work)
63 {
64         struct mpc8xxx_spi *mpc8xxx_spi = container_of(work, struct mpc8xxx_spi,
65                                                        work);
66
67         spin_lock_irq(&mpc8xxx_spi->lock);
68         while (!list_empty(&mpc8xxx_spi->queue)) {
69                 struct spi_message *m = container_of(mpc8xxx_spi->queue.next,
70                                                    struct spi_message, queue);
71
72                 list_del_init(&m->queue);
73                 spin_unlock_irq(&mpc8xxx_spi->lock);
74
75                 if (mpc8xxx_spi->spi_do_one_msg)
76                         mpc8xxx_spi->spi_do_one_msg(m);
77
78                 spin_lock_irq(&mpc8xxx_spi->lock);
79         }
80         spin_unlock_irq(&mpc8xxx_spi->lock);
81 }
82
83 int mpc8xxx_spi_transfer(struct spi_device *spi,
84                                 struct spi_message *m)
85 {
86         struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master);
87         unsigned long flags;
88
89         m->actual_length = 0;
90         m->status = -EINPROGRESS;
91
92         spin_lock_irqsave(&mpc8xxx_spi->lock, flags);
93         list_add_tail(&m->queue, &mpc8xxx_spi->queue);
94         queue_work(mpc8xxx_spi->workqueue, &mpc8xxx_spi->work);
95         spin_unlock_irqrestore(&mpc8xxx_spi->lock, flags);
96
97         return 0;
98 }
99
100 void mpc8xxx_spi_cleanup(struct spi_device *spi)
101 {
102         kfree(spi->controller_state);
103 }
104
105 const char *mpc8xxx_spi_strmode(unsigned int flags)
106 {
107         if (flags & SPI_QE_CPU_MODE) {
108                 return "QE CPU";
109         } else if (flags & SPI_CPM_MODE) {
110                 if (flags & SPI_QE)
111                         return "QE";
112                 else if (flags & SPI_CPM2)
113                         return "CPM2";
114                 else
115                         return "CPM1";
116         }
117         return "CPU";
118 }
119
120 int mpc8xxx_spi_probe(struct device *dev, struct resource *mem,
121                         unsigned int irq)
122 {
123         struct fsl_spi_platform_data *pdata = dev->platform_data;
124         struct spi_master *master;
125         struct mpc8xxx_spi *mpc8xxx_spi;
126         int ret = 0;
127
128         master = dev_get_drvdata(dev);
129
130         /* the spi->mode bits understood by this driver: */
131         master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH
132                         | SPI_LSB_FIRST | SPI_LOOP;
133
134         master->transfer = mpc8xxx_spi_transfer;
135         master->cleanup = mpc8xxx_spi_cleanup;
136         master->dev.of_node = dev->of_node;
137
138         mpc8xxx_spi = spi_master_get_devdata(master);
139         mpc8xxx_spi->dev = dev;
140         mpc8xxx_spi->get_rx = mpc8xxx_spi_rx_buf_u8;
141         mpc8xxx_spi->get_tx = mpc8xxx_spi_tx_buf_u8;
142         mpc8xxx_spi->flags = pdata->flags;
143         mpc8xxx_spi->spibrg = pdata->sysclk;
144         mpc8xxx_spi->irq = irq;
145
146         mpc8xxx_spi->rx_shift = 0;
147         mpc8xxx_spi->tx_shift = 0;
148
149         init_completion(&mpc8xxx_spi->done);
150
151         master->bus_num = pdata->bus_num;
152         master->num_chipselect = pdata->max_chipselect;
153
154         spin_lock_init(&mpc8xxx_spi->lock);
155         init_completion(&mpc8xxx_spi->done);
156         INIT_WORK(&mpc8xxx_spi->work, mpc8xxx_spi_work);
157         INIT_LIST_HEAD(&mpc8xxx_spi->queue);
158
159         mpc8xxx_spi->workqueue = create_singlethread_workqueue(
160                 dev_name(master->dev.parent));
161         if (mpc8xxx_spi->workqueue == NULL) {
162                 ret = -EBUSY;
163                 goto err;
164         }
165
166         return 0;
167
168 err:
169         return ret;
170 }
171
172 int __devexit mpc8xxx_spi_remove(struct device *dev)
173 {
174         struct mpc8xxx_spi *mpc8xxx_spi;
175         struct spi_master *master;
176
177         master = dev_get_drvdata(dev);
178         mpc8xxx_spi = spi_master_get_devdata(master);
179
180         flush_workqueue(mpc8xxx_spi->workqueue);
181         destroy_workqueue(mpc8xxx_spi->workqueue);
182         spi_unregister_master(master);
183
184         free_irq(mpc8xxx_spi->irq, mpc8xxx_spi);
185
186         if (mpc8xxx_spi->spi_remove)
187                 mpc8xxx_spi->spi_remove(mpc8xxx_spi);
188
189         return 0;
190 }
191
192 int __devinit of_mpc8xxx_spi_probe(struct platform_device *ofdev)
193 {
194         struct device *dev = &ofdev->dev;
195         struct device_node *np = ofdev->dev.of_node;
196         struct mpc8xxx_spi_probe_info *pinfo;
197         struct fsl_spi_platform_data *pdata;
198         const void *prop;
199         int ret = -ENOMEM;
200
201         pinfo = kzalloc(sizeof(*pinfo), GFP_KERNEL);
202         if (!pinfo)
203                 return -ENOMEM;
204
205         pdata = &pinfo->pdata;
206         dev->platform_data = pdata;
207
208         /* Allocate bus num dynamically. */
209         pdata->bus_num = -1;
210
211         /* SPI controller is either clocked from QE or SoC clock. */
212         pdata->sysclk = get_brgfreq();
213         if (pdata->sysclk == -1) {
214                 pdata->sysclk = fsl_get_sys_freq();
215                 if (pdata->sysclk == -1) {
216                         ret = -ENODEV;
217                         goto err;
218                 }
219         }
220
221         prop = of_get_property(np, "mode", NULL);
222         if (prop && !strcmp(prop, "cpu-qe"))
223                 pdata->flags = SPI_QE_CPU_MODE;
224         else if (prop && !strcmp(prop, "qe"))
225                 pdata->flags = SPI_CPM_MODE | SPI_QE;
226         else if (of_device_is_compatible(np, "fsl,cpm2-spi"))
227                 pdata->flags = SPI_CPM_MODE | SPI_CPM2;
228         else if (of_device_is_compatible(np, "fsl,cpm1-spi"))
229                 pdata->flags = SPI_CPM_MODE | SPI_CPM1;
230
231         return 0;
232
233 err:
234         kfree(pinfo);
235         return ret;
236 }