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-rw-r--r--drivers/parport/parport_gsc.c426
1 files changed, 426 insertions, 0 deletions
diff --git a/drivers/parport/parport_gsc.c b/drivers/parport/parport_gsc.c
new file mode 100644
index 000000000..0dcc497b0
--- /dev/null
+++ b/drivers/parport/parport_gsc.c
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+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Low-level parallel-support for PC-style hardware integrated in the
+ * LASI-Controller (on GSC-Bus) for HP-PARISC Workstations
+ *
+ * (C) 1999-2001 by Helge Deller <deller@gmx.de>
+ *
+ * based on parport_pc.c by
+ * Grant Guenther <grant@torque.net>
+ * Phil Blundell <philb@gnu.org>
+ * Tim Waugh <tim@cyberelk.demon.co.uk>
+ * Jose Renau <renau@acm.org>
+ * David Campbell
+ * Andrea Arcangeli
+ */
+
+#undef DEBUG /* undef for production */
+
+#include <linux/module.h>
+#include <linux/init.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/pci.h>
+#include <linux/sysctl.h>
+
+#include <asm/io.h>
+#include <asm/dma.h>
+#include <linux/uaccess.h>
+#include <asm/superio.h>
+
+#include <linux/parport.h>
+#include <asm/pdc.h>
+#include <asm/parisc-device.h>
+#include <asm/hardware.h>
+#include "parport_gsc.h"
+
+
+MODULE_AUTHOR("Helge Deller <deller@gmx.de>");
+MODULE_DESCRIPTION("HP-PARISC PC-style parallel port driver");
+MODULE_LICENSE("GPL");
+
+
+/*
+ * Clear TIMEOUT BIT in EPP MODE
+ *
+ * This is also used in SPP detection.
+ */
+static int clear_epp_timeout(struct parport *pb)
+{
+ unsigned char r;
+
+ if (!(parport_gsc_read_status(pb) & 0x01))
+ return 1;
+
+ /* To clear timeout some chips require double read */
+ parport_gsc_read_status(pb);
+ r = parport_gsc_read_status(pb);
+ parport_writeb (r | 0x01, STATUS (pb)); /* Some reset by writing 1 */
+ parport_writeb (r & 0xfe, STATUS (pb)); /* Others by writing 0 */
+ r = parport_gsc_read_status(pb);
+
+ return !(r & 0x01);
+}
+
+/*
+ * Access functions.
+ *
+ * Most of these aren't static because they may be used by the
+ * parport_xxx_yyy macros. extern __inline__ versions of several
+ * of these are in parport_gsc.h.
+ */
+
+void parport_gsc_init_state(struct pardevice *dev, struct parport_state *s)
+{
+ s->u.pc.ctr = 0xc | (dev->irq_func ? 0x10 : 0x0);
+}
+
+void parport_gsc_save_state(struct parport *p, struct parport_state *s)
+{
+ s->u.pc.ctr = parport_readb (CONTROL (p));
+}
+
+void parport_gsc_restore_state(struct parport *p, struct parport_state *s)
+{
+ parport_writeb (s->u.pc.ctr, CONTROL (p));
+}
+
+struct parport_operations parport_gsc_ops =
+{
+ .write_data = parport_gsc_write_data,
+ .read_data = parport_gsc_read_data,
+
+ .write_control = parport_gsc_write_control,
+ .read_control = parport_gsc_read_control,
+ .frob_control = parport_gsc_frob_control,
+
+ .read_status = parport_gsc_read_status,
+
+ .enable_irq = parport_gsc_enable_irq,
+ .disable_irq = parport_gsc_disable_irq,
+
+ .data_forward = parport_gsc_data_forward,
+ .data_reverse = parport_gsc_data_reverse,
+
+ .init_state = parport_gsc_init_state,
+ .save_state = parport_gsc_save_state,
+ .restore_state = parport_gsc_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,
+};
+
+/* --- Mode detection ------------------------------------- */
+
+/*
+ * Checks for port existence, all ports support SPP MODE
+ */
+static int parport_SPP_supported(struct parport *pb)
+{
+ unsigned char r, w;
+
+ /*
+ * first clear an eventually pending EPP timeout
+ * I (sailer@ife.ee.ethz.ch) have an SMSC chipset
+ * that does not even respond to SPP cycles if an EPP
+ * timeout is pending
+ */
+ clear_epp_timeout(pb);
+
+ /* Do a simple read-write test to make sure the port exists. */
+ w = 0xc;
+ parport_writeb (w, CONTROL (pb));
+
+ /* Is there a control register that we can read from? Some
+ * ports don't allow reads, so read_control just returns a
+ * software copy. Some ports _do_ allow reads, so bypass the
+ * software copy here. In addition, some bits aren't
+ * writable. */
+ r = parport_readb (CONTROL (pb));
+ if ((r & 0xf) == w) {
+ w = 0xe;
+ parport_writeb (w, CONTROL (pb));
+ r = parport_readb (CONTROL (pb));
+ parport_writeb (0xc, CONTROL (pb));
+ if ((r & 0xf) == w)
+ return PARPORT_MODE_PCSPP;
+ }
+
+ /* Try the data register. The data lines aren't tri-stated at
+ * this stage, so we expect back what we wrote. */
+ w = 0xaa;
+ parport_gsc_write_data (pb, w);
+ r = parport_gsc_read_data (pb);
+ if (r == w) {
+ w = 0x55;
+ parport_gsc_write_data (pb, w);
+ r = parport_gsc_read_data (pb);
+ if (r == w)
+ return PARPORT_MODE_PCSPP;
+ }
+
+ return 0;
+}
+
+/* Detect PS/2 support.
+ *
+ * Bit 5 (0x20) sets the PS/2 data direction; setting this high
+ * allows us to read data from the data lines. In theory we would get back
+ * 0xff but any peripheral attached to the port may drag some or all of the
+ * lines down to zero. So if we get back anything that isn't the contents
+ * of the data register we deem PS/2 support to be present.
+ *
+ * Some SPP ports have "half PS/2" ability - you can't turn off the line
+ * drivers, but an external peripheral with sufficiently beefy drivers of
+ * its own can overpower them and assert its own levels onto the bus, from
+ * where they can then be read back as normal. Ports with this property
+ * and the right type of device attached are likely to fail the SPP test,
+ * (as they will appear to have stuck bits) and so the fact that they might
+ * be misdetected here is rather academic.
+ */
+
+static int parport_PS2_supported(struct parport *pb)
+{
+ int ok = 0;
+
+ clear_epp_timeout(pb);
+
+ /* try to tri-state the buffer */
+ parport_gsc_data_reverse (pb);
+
+ parport_gsc_write_data(pb, 0x55);
+ if (parport_gsc_read_data(pb) != 0x55) ok++;
+
+ parport_gsc_write_data(pb, 0xaa);
+ if (parport_gsc_read_data(pb) != 0xaa) ok++;
+
+ /* cancel input mode */
+ parport_gsc_data_forward (pb);
+
+ if (ok) {
+ pb->modes |= PARPORT_MODE_TRISTATE;
+ } else {
+ struct parport_gsc_private *priv = pb->private_data;
+ priv->ctr_writable &= ~0x20;
+ }
+
+ return ok;
+}
+
+
+/* --- Initialisation code -------------------------------- */
+
+struct parport *parport_gsc_probe_port(unsigned long base,
+ unsigned long base_hi, int irq,
+ int dma, struct parisc_device *padev)
+{
+ struct parport_gsc_private *priv;
+ struct parport_operations *ops;
+ struct parport tmp;
+ struct parport *p = &tmp;
+
+ priv = kzalloc (sizeof (struct parport_gsc_private), GFP_KERNEL);
+ if (!priv) {
+ printk(KERN_DEBUG "parport (0x%lx): no memory!\n", base);
+ return NULL;
+ }
+ ops = kmemdup(&parport_gsc_ops, sizeof(struct parport_operations),
+ GFP_KERNEL);
+ if (!ops) {
+ printk(KERN_DEBUG "parport (0x%lx): no memory for ops!\n",
+ base);
+ kfree (priv);
+ return NULL;
+ }
+ priv->ctr = 0xc;
+ priv->ctr_writable = 0xff;
+ priv->dma_buf = NULL;
+ priv->dma_handle = 0;
+ p->base = base;
+ p->base_hi = base_hi;
+ p->irq = irq;
+ p->dma = dma;
+ p->modes = PARPORT_MODE_PCSPP | PARPORT_MODE_SAFEININT;
+ p->ops = ops;
+ p->private_data = priv;
+ p->physport = p;
+ if (!parport_SPP_supported (p)) {
+ /* No port. */
+ kfree (priv);
+ kfree(ops);
+ return NULL;
+ }
+ parport_PS2_supported (p);
+
+ if (!(p = parport_register_port(base, PARPORT_IRQ_NONE,
+ PARPORT_DMA_NONE, ops))) {
+ kfree (priv);
+ kfree (ops);
+ return NULL;
+ }
+
+ p->dev = &padev->dev;
+ p->base_hi = base_hi;
+ p->modes = tmp.modes;
+ p->size = (p->modes & PARPORT_MODE_EPP)?8:3;
+ p->private_data = priv;
+
+ pr_info("%s: PC-style at 0x%lx", p->name, p->base);
+ p->irq = irq;
+ if (p->irq == PARPORT_IRQ_AUTO) {
+ p->irq = PARPORT_IRQ_NONE;
+ }
+ if (p->irq != PARPORT_IRQ_NONE) {
+ pr_cont(", irq %d", p->irq);
+
+ if (p->dma == PARPORT_DMA_AUTO) {
+ p->dma = PARPORT_DMA_NONE;
+ }
+ }
+ if (p->dma == PARPORT_DMA_AUTO) /* To use DMA, giving the irq
+ is mandatory (see above) */
+ p->dma = PARPORT_DMA_NONE;
+
+ pr_cont(" [");
+#define printmode(x) \
+do { \
+ if (p->modes & PARPORT_MODE_##x) \
+ pr_cont("%s%s", f++ ? "," : "", #x); \
+} while (0)
+ {
+ int f = 0;
+ printmode(PCSPP);
+ printmode(TRISTATE);
+ printmode(COMPAT);
+ printmode(EPP);
+// printmode(ECP);
+// printmode(DMA);
+ }
+#undef printmode
+ pr_cont("]\n");
+
+ if (p->irq != PARPORT_IRQ_NONE) {
+ if (request_irq (p->irq, parport_irq_handler,
+ 0, p->name, p)) {
+ pr_warn("%s: irq %d in use, resorting to polled operation\n",
+ p->name, p->irq);
+ p->irq = PARPORT_IRQ_NONE;
+ p->dma = PARPORT_DMA_NONE;
+ }
+ }
+
+ /* Done probing. Now put the port into a sensible start-up state. */
+
+ parport_gsc_write_data(p, 0);
+ parport_gsc_data_forward (p);
+
+ /* Now that we've told the sharing engine about the port, and
+ found out its characteristics, let the high-level drivers
+ know about it. */
+ parport_announce_port (p);
+
+ return p;
+}
+
+
+#define PARPORT_GSC_OFFSET 0x800
+
+static int parport_count;
+
+static int __init parport_init_chip(struct parisc_device *dev)
+{
+ struct parport *p;
+ unsigned long port;
+
+ if (!dev->irq) {
+ pr_warn("IRQ not found for parallel device at 0x%llx\n",
+ (unsigned long long)dev->hpa.start);
+ return -ENODEV;
+ }
+
+ port = dev->hpa.start + PARPORT_GSC_OFFSET;
+
+ /* some older machines with ASP-chip don't support
+ * the enhanced parport modes.
+ */
+ if (boot_cpu_data.cpu_type > pcxt && !pdc_add_valid(port+4)) {
+
+ /* Initialize bidirectional-mode (0x10) & data-tranfer-mode #1 (0x20) */
+ pr_info("%s: initialize bidirectional-mode\n", __func__);
+ parport_writeb ( (0x10 + 0x20), port + 4);
+
+ } else {
+ pr_info("%s: enhanced parport-modes not supported\n", __func__);
+ }
+
+ p = parport_gsc_probe_port(port, 0, dev->irq,
+ /* PARPORT_IRQ_NONE */ PARPORT_DMA_NONE, dev);
+ if (p)
+ parport_count++;
+ dev_set_drvdata(&dev->dev, p);
+
+ return 0;
+}
+
+static void __exit parport_remove_chip(struct parisc_device *dev)
+{
+ struct parport *p = dev_get_drvdata(&dev->dev);
+ if (p) {
+ struct parport_gsc_private *priv = p->private_data;
+ struct parport_operations *ops = p->ops;
+ parport_remove_port(p);
+ if (p->dma != PARPORT_DMA_NONE)
+ free_dma(p->dma);
+ if (p->irq != PARPORT_IRQ_NONE)
+ free_irq(p->irq, p);
+ if (priv->dma_buf)
+ dma_free_coherent(&priv->dev->dev, PAGE_SIZE,
+ priv->dma_buf, priv->dma_handle);
+ kfree (p->private_data);
+ parport_put_port(p);
+ kfree (ops); /* hope no-one cached it */
+ }
+}
+
+static const struct parisc_device_id parport_tbl[] __initconst = {
+ { HPHW_FIO, HVERSION_REV_ANY_ID, HVERSION_ANY_ID, 0x74 },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE(parisc, parport_tbl);
+
+static struct parisc_driver parport_driver __refdata = {
+ .name = "Parallel",
+ .id_table = parport_tbl,
+ .probe = parport_init_chip,
+ .remove = __exit_p(parport_remove_chip),
+};
+
+int parport_gsc_init(void)
+{
+ return register_parisc_driver(&parport_driver);
+}
+
+static void parport_gsc_exit(void)
+{
+ unregister_parisc_driver(&parport_driver);
+}
+
+module_init(parport_gsc_init);
+module_exit(parport_gsc_exit);
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