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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/i2c/busses/i2c-pca-isa.c
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/i2c/busses/i2c-pca-isa.c')
-rw-r--r--drivers/i2c/busses/i2c-pca-isa.c184
1 files changed, 184 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-pca-isa.c b/drivers/i2c/busses/i2c-pca-isa.c
new file mode 100644
index 00000000000..9c611134db9
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pca-isa.c
@@ -0,0 +1,184 @@
+/*
+ * i2c-pca-isa.c driver for PCA9564 on ISA boards
+ * Copyright (C) 2004 Arcom Control Systems
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/wait.h>
+
+#include <linux/i2c.h>
+#include <linux/i2c-algo-pca.h>
+
+#include <asm/io.h>
+#include <asm/irq.h>
+
+#include "../algos/i2c-algo-pca.h"
+
+#define IO_SIZE 4
+
+#undef DEBUG_IO
+//#define DEBUG_IO
+
+static unsigned long base = 0x330;
+static int irq = 10;
+
+/* Data sheet recommends 59kHz for 100kHz operation due to variation
+ * in the actual clock rate */
+static int clock = I2C_PCA_CON_59kHz;
+
+static int own = 0x55;
+
+static wait_queue_head_t pca_wait;
+
+static int pca_isa_getown(struct i2c_algo_pca_data *adap)
+{
+ return (own);
+}
+
+static int pca_isa_getclock(struct i2c_algo_pca_data *adap)
+{
+ return (clock);
+}
+
+static void
+pca_isa_writebyte(struct i2c_algo_pca_data *adap, int reg, int val)
+{
+#ifdef DEBUG_IO
+ static char *names[] = { "T/O", "DAT", "ADR", "CON" };
+ printk("*** write %s at %#lx <= %#04x\n", names[reg], base+reg, val);
+#endif
+ outb(val, base+reg);
+}
+
+static int
+pca_isa_readbyte(struct i2c_algo_pca_data *adap, int reg)
+{
+ int res = inb(base+reg);
+#ifdef DEBUG_IO
+ {
+ static char *names[] = { "STA", "DAT", "ADR", "CON" };
+ printk("*** read %s => %#04x\n", names[reg], res);
+ }
+#endif
+ return res;
+}
+
+static int pca_isa_waitforinterrupt(struct i2c_algo_pca_data *adap)
+{
+ int ret = 0;
+
+ if (irq > -1) {
+ ret = wait_event_interruptible(pca_wait,
+ pca_isa_readbyte(adap, I2C_PCA_CON) & I2C_PCA_CON_SI);
+ } else {
+ while ((pca_isa_readbyte(adap, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
+ udelay(100);
+ }
+ return ret;
+}
+
+static irqreturn_t pca_handler(int this_irq, void *dev_id, struct pt_regs *regs) {
+ wake_up_interruptible(&pca_wait);
+ return IRQ_HANDLED;
+}
+
+static struct i2c_algo_pca_data pca_isa_data = {
+ .get_own = pca_isa_getown,
+ .get_clock = pca_isa_getclock,
+ .write_byte = pca_isa_writebyte,
+ .read_byte = pca_isa_readbyte,
+ .wait_for_interrupt = pca_isa_waitforinterrupt,
+};
+
+static struct i2c_adapter pca_isa_ops = {
+ .owner = THIS_MODULE,
+ .id = I2C_HW_A_ISA,
+ .algo_data = &pca_isa_data,
+ .name = "PCA9564 ISA Adapter",
+};
+
+static int __init pca_isa_init(void)
+{
+
+ init_waitqueue_head(&pca_wait);
+
+ printk(KERN_INFO "i2c-pca-isa: i/o base %#08lx. irq %d\n", base, irq);
+
+ if (!request_region(base, IO_SIZE, "i2c-pca-isa")) {
+ printk(KERN_ERR "i2c-pca-isa: I/O address %#08lx is in use.\n", base);
+ goto out;
+ }
+
+ if (irq > -1) {
+ if (request_irq(irq, pca_handler, 0, "i2c-pca-isa", &pca_isa_ops) < 0) {
+ printk(KERN_ERR "i2c-pca-isa: Request irq%d failed\n", irq);
+ goto out_region;
+ }
+ }
+
+ if (i2c_pca_add_bus(&pca_isa_ops) < 0) {
+ printk(KERN_ERR "i2c-pca-isa: Failed to add i2c bus\n");
+ goto out_irq;
+ }
+
+ return 0;
+
+ out_irq:
+ if (irq > -1)
+ free_irq(irq, &pca_isa_ops);
+ out_region:
+ release_region(base, IO_SIZE);
+ out:
+ return -ENODEV;
+}
+
+static void pca_isa_exit(void)
+{
+ i2c_pca_del_bus(&pca_isa_ops);
+
+ if (irq > 0) {
+ disable_irq(irq);
+ free_irq(irq, &pca_isa_ops);
+ }
+ release_region(base, IO_SIZE);
+}
+
+MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>");
+MODULE_DESCRIPTION("ISA base PCA9564 driver");
+MODULE_LICENSE("GPL");
+
+module_param(base, ulong, 0);
+MODULE_PARM_DESC(base, "I/O base address");
+
+module_param(irq, int, 0);
+MODULE_PARM_DESC(irq, "IRQ");
+module_param(clock, int, 0);
+MODULE_PARM_DESC(clock, "Clock rate as described in table 1 of PCA9564 datasheet");
+
+module_param(own, int, 0); /* the driver can't do slave mode, so there's no real point in this */
+
+module_init(pca_isa_init);
+module_exit(pca_isa_exit);