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-rw-r--r--drivers/i2c/busses/i2c-hydra.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-hydra.c b/drivers/i2c/busses/i2c-hydra.c
new file mode 100644
index 0000000000..c60b73e933
--- /dev/null
+++ b/drivers/i2c/busses/i2c-hydra.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ i2c Support for the Apple `Hydra' Mac I/O
+
+ Copyright (c) 1999-2004 Geert Uytterhoeven <geert@linux-m68k.org>
+
+ Based on i2c Support for Via Technologies 82C586B South Bridge
+ Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi>
+
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/types.h>
+#include <linux/i2c.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/io.h>
+#include <asm/hydra.h>
+
+
+#define HYDRA_CPD_PD0 0x00000001 /* CachePD lines */
+#define HYDRA_CPD_PD1 0x00000002
+#define HYDRA_CPD_PD2 0x00000004
+#define HYDRA_CPD_PD3 0x00000008
+
+#define HYDRA_SCLK HYDRA_CPD_PD0
+#define HYDRA_SDAT HYDRA_CPD_PD1
+#define HYDRA_SCLK_OE 0x00000010
+#define HYDRA_SDAT_OE 0x00000020
+
+static inline void pdregw(void *data, u32 val)
+{
+ struct Hydra *hydra = (struct Hydra *)data;
+ writel(val, &hydra->CachePD);
+}
+
+static inline u32 pdregr(void *data)
+{
+ struct Hydra *hydra = (struct Hydra *)data;
+ return readl(&hydra->CachePD);
+}
+
+static void hydra_bit_setscl(void *data, int state)
+{
+ u32 val = pdregr(data);
+ if (state)
+ val &= ~HYDRA_SCLK_OE;
+ else {
+ val &= ~HYDRA_SCLK;
+ val |= HYDRA_SCLK_OE;
+ }
+ pdregw(data, val);
+}
+
+static void hydra_bit_setsda(void *data, int state)
+{
+ u32 val = pdregr(data);
+ if (state)
+ val &= ~HYDRA_SDAT_OE;
+ else {
+ val &= ~HYDRA_SDAT;
+ val |= HYDRA_SDAT_OE;
+ }
+ pdregw(data, val);
+}
+
+static int hydra_bit_getscl(void *data)
+{
+ return (pdregr(data) & HYDRA_SCLK) != 0;
+}
+
+static int hydra_bit_getsda(void *data)
+{
+ return (pdregr(data) & HYDRA_SDAT) != 0;
+}
+
+/* ------------------------------------------------------------------------ */
+
+static struct i2c_algo_bit_data hydra_bit_data = {
+ .setsda = hydra_bit_setsda,
+ .setscl = hydra_bit_setscl,
+ .getsda = hydra_bit_getsda,
+ .getscl = hydra_bit_getscl,
+ .udelay = 5,
+ .timeout = HZ
+};
+
+static struct i2c_adapter hydra_adap = {
+ .owner = THIS_MODULE,
+ .name = "Hydra i2c",
+ .algo_data = &hydra_bit_data,
+};
+
+static const struct pci_device_id hydra_ids[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_HYDRA) },
+ { 0, }
+};
+
+MODULE_DEVICE_TABLE (pci, hydra_ids);
+
+static int hydra_probe(struct pci_dev *dev,
+ const struct pci_device_id *id)
+{
+ unsigned long base = pci_resource_start(dev, 0);
+ int res;
+
+ if (!request_mem_region(base+offsetof(struct Hydra, CachePD), 4,
+ hydra_adap.name))
+ return -EBUSY;
+
+ hydra_bit_data.data = pci_ioremap_bar(dev, 0);
+ if (hydra_bit_data.data == NULL) {
+ release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
+ return -ENODEV;
+ }
+
+ pdregw(hydra_bit_data.data, 0); /* clear SCLK_OE and SDAT_OE */
+ hydra_adap.dev.parent = &dev->dev;
+ res = i2c_bit_add_bus(&hydra_adap);
+ if (res < 0) {
+ iounmap(hydra_bit_data.data);
+ release_mem_region(base+offsetof(struct Hydra, CachePD), 4);
+ return res;
+ }
+ return 0;
+}
+
+static void hydra_remove(struct pci_dev *dev)
+{
+ pdregw(hydra_bit_data.data, 0); /* clear SCLK_OE and SDAT_OE */
+ i2c_del_adapter(&hydra_adap);
+ iounmap(hydra_bit_data.data);
+ release_mem_region(pci_resource_start(dev, 0)+
+ offsetof(struct Hydra, CachePD), 4);
+}
+
+
+static struct pci_driver hydra_driver = {
+ .name = "hydra_smbus",
+ .id_table = hydra_ids,
+ .probe = hydra_probe,
+ .remove = hydra_remove,
+};
+
+module_pci_driver(hydra_driver);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert@linux-m68k.org>");
+MODULE_DESCRIPTION("i2c for Apple Hydra Mac I/O");
+MODULE_LICENSE("GPL");