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-rw-r--r--drivers/parport/parport_arc.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/parport/parport_arc.c b/drivers/parport/parport_arc.c
new file mode 100644
index 0000000..b35bb4f
--- /dev/null
+++ b/drivers/parport/parport_arc.c
@@ -0,0 +1,139 @@
+/* Low-level parallel port routines for Archimedes onboard hardware
+ *
+ * Author: Phil Blundell <philb@gnu.org>
+ */
+
+/* This driver is for the parallel port hardware found on Acorn's old
+ * range of Archimedes machines. The A5000 and newer systems have PC-style
+ * I/O hardware and should use the parport_pc driver instead.
+ *
+ * The Acorn printer port hardware is very simple. There is a single 8-bit
+ * write-only latch for the data port and control/status bits are handled
+ * with various auxilliary input and output lines. The port is not
+ * bidirectional, does not support any modes other than SPP, and has only
+ * a subset of the standard printer control lines connected.
+ */
+
+#include <linux/threads.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/parport.h>
+
+#include <asm/ptrace.h>
+#include <asm/io.h>
+#include <asm/arch/oldlatches.h>
+#include <asm/arch/irqs.h>
+
+#define DATA_ADDRESS 0x3350010
+
+/* This is equivalent to the above and only used for request_region. */
+#define PORT_BASE 0x80000000 | ((DATA_ADDRESS - IO_BASE) >> 2)
+
+/* The hardware can't read from the data latch, so we must use a soft
+ copy. */
+static unsigned char data_copy;
+
+/* These are pretty simple. We know the irq is never shared and the
+ kernel does all the magic that's required. */
+static void arc_enable_irq(struct parport *p)
+{
+ enable_irq(p->irq);
+}
+
+static void arc_disable_irq(struct parport *p)
+{
+ disable_irq(p->irq);
+}
+
+static void arc_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ parport_generic_irq(irq, (struct parport *) dev_id, regs);
+}
+
+static void arc_write_data(struct parport *p, unsigned char data)
+{
+ data_copy = data;
+ outb_t(data, DATA_LATCH);
+}
+
+static unsigned char arc_read_data(struct parport *p)
+{
+ return data_copy;
+}
+
+static struct parport_operations parport_arc_ops =
+{
+ .write_data = arc_write_data,
+ .read_data = arc_read_data,
+
+ .write_control = arc_write_control,
+ .read_control = arc_read_control,
+ .frob_control = arc_frob_control,
+
+ .read_status = arc_read_status,
+
+ .enable_irq = arc_enable_irq,
+ .disable_irq = arc_disable_irq,
+
+ .data_forward = arc_data_forward,
+ .data_reverse = arc_data_reverse,
+
+ .init_state = arc_init_state,
+ .save_state = arc_save_state,
+ .restore_state = arc_restore_state,
+
+ .epp_write_data = parport_ieee1284_epp_write_data,
+ .epp_read_data = parport_ieee1284_epp_read_data,
+ .epp_write_addr = parport_ieee1284_epp_write_addr,
+ .epp_read_addr = parport_ieee1284_epp_read_addr,
+
+ .ecp_write_data = parport_ieee1284_ecp_write_data,
+ .ecp_read_data = parport_ieee1284_ecp_read_data,
+ .ecp_write_addr = parport_ieee1284_ecp_write_addr,
+
+ .compat_write_data = parport_ieee1284_write_compat,
+ .nibble_read_data = parport_ieee1284_read_nibble,
+ .byte_read_data = parport_ieee1284_read_byte,
+
+ .owner = THIS_MODULE,
+};
+
+/* --- Initialisation code -------------------------------- */
+
+static int parport_arc_init(void)
+{
+ /* Archimedes hardware provides only one port, at a fixed address */
+ struct parport *p;
+ struct resource res;
+ char *fake_name = "parport probe");
+
+ res = request_region(PORT_BASE, 1, fake_name);
+ if (res == NULL)
+ return 0;
+
+ p = parport_register_port (PORT_BASE, IRQ_PRINTERACK,
+ PARPORT_DMA_NONE, &parport_arc_ops);
+
+ if (!p) {
+ release_region(PORT_BASE, 1);
+ return 0;
+ }
+
+ p->modes = PARPORT_MODE_ARCSPP;
+ p->size = 1;
+ rename_region(res, p->name);
+
+ printk(KERN_INFO "%s: Archimedes on-board port, using irq %d\n",
+ p->irq);
+
+ /* Tell the high-level drivers about the port. */
+ parport_announce_port (p);
+
+ return 1;
+}
+
+module_init(parport_arc_init)