cx88-vp3054-i2c.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * cx88-vp3054-i2c.c -- support for the secondary I2C bus of the
  4 *			DNTV Live! DVB-T Pro (VP-3054), wired as:
  5 *			GPIO[0] -> SCL, GPIO[1] -> SDA
  6 *
  7 * (c) 2005 Chris Pascoe <c.pascoe@itee.uq.edu.au>
  8 */
  9
 10#include "cx88.h"
 11#include "cx88-vp3054-i2c.h"
 12
 13#include <linux/module.h>
 14#include <linux/slab.h>
 15#include <linux/init.h>
 16#include <linux/io.h>
 17
 18MODULE_DESCRIPTION("driver for cx2388x VP3054 design");
 19MODULE_AUTHOR("Chris Pascoe <c.pascoe@itee.uq.edu.au>");
 20MODULE_LICENSE("GPL");
 21
 22/* ----------------------------------------------------------------------- */
 23
 24static void vp3054_bit_setscl(void *data, int state)
 25{
 26	struct cx8802_dev *dev = data;
 27	struct cx88_core *core = dev->core;
 28	struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
 29
 30	if (state) {
 31		vp3054_i2c->state |=  0x0001;	/* SCL high */
 32		vp3054_i2c->state &= ~0x0100;	/* external pullup */
 33	} else {
 34		vp3054_i2c->state &= ~0x0001;	/* SCL low */
 35		vp3054_i2c->state |=  0x0100;	/* drive pin */
 36	}
 37	cx_write(MO_GP0_IO, 0x010000 | vp3054_i2c->state);
 38	cx_read(MO_GP0_IO);
 39}
 40
 41static void vp3054_bit_setsda(void *data, int state)
 42{
 43	struct cx8802_dev *dev = data;
 44	struct cx88_core *core = dev->core;
 45	struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
 46
 47	if (state) {
 48		vp3054_i2c->state |=  0x0002;	/* SDA high */
 49		vp3054_i2c->state &= ~0x0200;	/* tristate pin */
 50	} else {
 51		vp3054_i2c->state &= ~0x0002;	/* SDA low */
 52		vp3054_i2c->state |=  0x0200;	/* drive pin */
 53	}
 54	cx_write(MO_GP0_IO, 0x020000 | vp3054_i2c->state);
 55	cx_read(MO_GP0_IO);
 56}
 57
 58static int vp3054_bit_getscl(void *data)
 59{
 60	struct cx8802_dev *dev = data;
 61	struct cx88_core *core = dev->core;
 62	u32 state;
 63
 64	state = cx_read(MO_GP0_IO);
 65	return (state & 0x01) ? 1 : 0;
 66}
 67
 68static int vp3054_bit_getsda(void *data)
 69{
 70	struct cx8802_dev *dev = data;
 71	struct cx88_core *core = dev->core;
 72	u32 state;
 73
 74	state = cx_read(MO_GP0_IO);
 75	return (state & 0x02) ? 1 : 0;
 76}
 77
 78/* ----------------------------------------------------------------------- */
 79
 80static const struct i2c_algo_bit_data vp3054_i2c_algo_template = {
 81	.setsda  = vp3054_bit_setsda,
 82	.setscl  = vp3054_bit_setscl,
 83	.getsda  = vp3054_bit_getsda,
 84	.getscl  = vp3054_bit_getscl,
 85	.udelay  = 16,
 86	.timeout = 200,
 87};
 88
 89/* ----------------------------------------------------------------------- */
 90
 91int vp3054_i2c_probe(struct cx8802_dev *dev)
 92{
 93	struct cx88_core *core = dev->core;
 94	struct vp3054_i2c_state *vp3054_i2c;
 95	int rc;
 96
 97	if (core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
 98		return 0;
 99
100	vp3054_i2c = kzalloc(sizeof(*vp3054_i2c), GFP_KERNEL);
101	if (!vp3054_i2c)
102		return -ENOMEM;
103	dev->vp3054 = vp3054_i2c;
104
105	vp3054_i2c->algo = vp3054_i2c_algo_template;
106
107	vp3054_i2c->adap.dev.parent = &dev->pci->dev;
108	strscpy(vp3054_i2c->adap.name, core->name,
109		sizeof(vp3054_i2c->adap.name));
110	vp3054_i2c->adap.owner = THIS_MODULE;
111	vp3054_i2c->algo.data = dev;
112	i2c_set_adapdata(&vp3054_i2c->adap, dev);
113	vp3054_i2c->adap.algo_data = &vp3054_i2c->algo;
114
115	vp3054_bit_setscl(dev, 1);
116	vp3054_bit_setsda(dev, 1);
117
118	rc = i2c_bit_add_bus(&vp3054_i2c->adap);
119	if (rc != 0) {
120		pr_err("vp3054_i2c register FAILED\n");
121
122		kfree(dev->vp3054);
123		dev->vp3054 = NULL;
124	}
125
126	return rc;
127}
128EXPORT_SYMBOL(vp3054_i2c_probe);
129
130void vp3054_i2c_remove(struct cx8802_dev *dev)
131{
132	struct vp3054_i2c_state *vp3054_i2c = dev->vp3054;
133
134	if (!vp3054_i2c ||
135	    dev->core->boardnr != CX88_BOARD_DNTV_LIVE_DVB_T_PRO)
136		return;
137
138	i2c_del_adapter(&vp3054_i2c->adap);
139	kfree(vp3054_i2c);
140}
141EXPORT_SYMBOL(vp3054_i2c_remove);