1 /*
2 * Copyright (C) 2012 CERN (www.cern.ch)
3 * Author: Alessandro Rubini <rubini@gnudd.com>
4 *
5 * Permission to use, copy, modify, and/or distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * The software is provided "as is"; the copyright holders disclaim
10 * all warranties and liabilities, to the extent permitted by
11 * applicable law.
12 */
13
14 /* A trivial fmc driver that can load a gateware file and reports interrupts */
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/interrupt.h>
18 #include <linux/gpio.h>
19 #include <linux/fmc.h>
20
21 static struct fmc_driver t_drv; /* initialized later */
22
t_handler(int irq,void * dev_id)23 static irqreturn_t t_handler(int irq, void *dev_id)
24 {
25 struct fmc_device *fmc = dev_id;
26
27 fmc->op->irq_ack(fmc);
28 dev_info(&fmc->dev, "received irq %i\n", irq);
29 return IRQ_HANDLED;
30 }
31
32 static struct fmc_gpio t_gpio[] = {
33 {
34 .gpio = FMC_GPIO_IRQ(0),
35 .mode = GPIOF_DIR_IN,
36 .irqmode = IRQF_TRIGGER_RISING,
37 }, {
38 .gpio = FMC_GPIO_IRQ(1),
39 .mode = GPIOF_DIR_IN,
40 .irqmode = IRQF_TRIGGER_RISING,
41 }
42 };
43
t_probe(struct fmc_device * fmc)44 static int t_probe(struct fmc_device *fmc)
45 {
46 int ret;
47 int index = 0;
48
49 if (fmc->op->validate)
50 index = fmc->op->validate(fmc, &t_drv);
51 if (index < 0)
52 return -EINVAL; /* not our device: invalid */
53
54 ret = fmc->op->irq_request(fmc, t_handler, "fmc-trivial", IRQF_SHARED);
55 if (ret < 0)
56 return ret;
57 /* ignore error code of call below, we really don't care */
58 fmc->op->gpio_config(fmc, t_gpio, ARRAY_SIZE(t_gpio));
59
60 /* Reprogram, if asked to. ESRCH == no filename specified */
61 ret = -ESRCH;
62 if (fmc->op->reprogram)
63 ret = fmc->op->reprogram(fmc, &t_drv, "");
64 if (ret == -ESRCH)
65 ret = 0;
66 if (ret < 0)
67 fmc->op->irq_free(fmc);
68
69 /* FIXME: reprogram LM32 too */
70 return ret;
71 }
72
t_remove(struct fmc_device * fmc)73 static int t_remove(struct fmc_device *fmc)
74 {
75 fmc->op->irq_free(fmc);
76 return 0;
77 }
78
79 static struct fmc_driver t_drv = {
80 .version = FMC_VERSION,
81 .driver.name = KBUILD_MODNAME,
82 .probe = t_probe,
83 .remove = t_remove,
84 /* no table, as the current match just matches everything */
85 };
86
87 /* We accept the generic parameters */
88 FMC_PARAM_BUSID(t_drv);
89 FMC_PARAM_GATEWARE(t_drv);
90
t_init(void)91 static int t_init(void)
92 {
93 int ret;
94
95 ret = fmc_driver_register(&t_drv);
96 return ret;
97 }
98
t_exit(void)99 static void t_exit(void)
100 {
101 fmc_driver_unregister(&t_drv);
102 }
103
104 module_init(t_init);
105 module_exit(t_exit);
106
107 MODULE_LICENSE("Dual BSD/GPL");
108