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!
diff --git a/drivers/i2c/busses/i2c-au1550.c b/drivers/i2c/busses/i2c-au1550.c
new file mode 100644
index 0000000..75831a20
--- /dev/null
+++ b/drivers/i2c/busses/i2c-au1550.c
@@ -0,0 +1,435 @@
+/*
+ * i2c-au1550.c: SMBus (i2c) adapter for Alchemy PSC interface
+ * Copyright (C) 2004 Embedded Edge, LLC <dan@embeddededge.com>
+ *
+ * 2.6 port by Matt Porter <mporter@kernel.crashing.org>
+ *
+ * The documentation describes this as an SMBus controller, but it doesn't
+ * understand any of the SMBus protocol in hardware. It's really an I2C
+ * controller that could emulate most of the SMBus in software.
+ *
+ * This is just a skeleton adapter to use with the Au1550 PSC
+ * algorithm. It was developed for the Pb1550, but will work with
+ * any Au1550 board that has a similar PSC configuration.
+ *
+ * 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <linux/config.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/i2c.h>
+
+#include <asm/mach-au1x00/au1000.h>
+#include <asm/mach-pb1x00/pb1550.h>
+#include <asm/mach-au1x00/au1xxx_psc.h>
+
+#include "i2c-au1550.h"
+
+static int
+wait_xfer_done(struct i2c_au1550_data *adap)
+{
+ u32 stat;
+ int i;
+ volatile psc_smb_t *sp;
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ /* Wait for Tx FIFO Underflow.
+ */
+ for (i = 0; i < adap->xfer_timeout; i++) {
+ stat = sp->psc_smbevnt;
+ au_sync();
+ if ((stat & PSC_SMBEVNT_TU) != 0) {
+ /* Clear it. */
+ sp->psc_smbevnt = PSC_SMBEVNT_TU;
+ au_sync();
+ return 0;
+ }
+ udelay(1);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static int
+wait_ack(struct i2c_au1550_data *adap)
+{
+ u32 stat;
+ volatile psc_smb_t *sp;
+
+ if (wait_xfer_done(adap))
+ return -ETIMEDOUT;
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ stat = sp->psc_smbevnt;
+ au_sync();
+
+ if ((stat & (PSC_SMBEVNT_DN | PSC_SMBEVNT_AN | PSC_SMBEVNT_AL)) != 0)
+ return -ETIMEDOUT;
+
+ return 0;
+}
+
+static int
+wait_master_done(struct i2c_au1550_data *adap)
+{
+ u32 stat;
+ int i;
+ volatile psc_smb_t *sp;
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ /* Wait for Master Done.
+ */
+ for (i = 0; i < adap->xfer_timeout; i++) {
+ stat = sp->psc_smbevnt;
+ au_sync();
+ if ((stat & PSC_SMBEVNT_MD) != 0)
+ return 0;
+ udelay(1);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static int
+do_address(struct i2c_au1550_data *adap, unsigned int addr, int rd)
+{
+ volatile psc_smb_t *sp;
+ u32 stat;
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ /* Reset the FIFOs, clear events.
+ */
+ sp->psc_smbpcr = PSC_SMBPCR_DC;
+ sp->psc_smbevnt = PSC_SMBEVNT_ALLCLR;
+ au_sync();
+ do {
+ stat = sp->psc_smbpcr;
+ au_sync();
+ } while ((stat & PSC_SMBPCR_DC) != 0);
+
+ /* Write out the i2c chip address and specify operation
+ */
+ addr <<= 1;
+ if (rd)
+ addr |= 1;
+
+ /* Put byte into fifo, start up master.
+ */
+ sp->psc_smbtxrx = addr;
+ au_sync();
+ sp->psc_smbpcr = PSC_SMBPCR_MS;
+ au_sync();
+ if (wait_ack(adap))
+ return -EIO;
+ return 0;
+}
+
+static u32
+wait_for_rx_byte(struct i2c_au1550_data *adap, u32 *ret_data)
+{
+ int j;
+ u32 data, stat;
+ volatile psc_smb_t *sp;
+
+ if (wait_xfer_done(adap))
+ return -EIO;
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ j = adap->xfer_timeout * 100;
+ do {
+ j--;
+ if (j <= 0)
+ return -EIO;
+
+ stat = sp->psc_smbstat;
+ au_sync();
+ if ((stat & PSC_SMBSTAT_RE) == 0)
+ j = 0;
+ else
+ udelay(1);
+ } while (j > 0);
+ data = sp->psc_smbtxrx;
+ au_sync();
+ *ret_data = data;
+
+ return 0;
+}
+
+static int
+i2c_read(struct i2c_au1550_data *adap, unsigned char *buf,
+ unsigned int len)
+{
+ int i;
+ u32 data;
+ volatile psc_smb_t *sp;
+
+ if (len == 0)
+ return 0;
+
+ /* A read is performed by stuffing the transmit fifo with
+ * zero bytes for timing, waiting for bytes to appear in the
+ * receive fifo, then reading the bytes.
+ */
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ i = 0;
+ while (i < (len-1)) {
+ sp->psc_smbtxrx = 0;
+ au_sync();
+ if (wait_for_rx_byte(adap, &data))
+ return -EIO;
+
+ buf[i] = data;
+ i++;
+ }
+
+ /* The last byte has to indicate transfer done.
+ */
+ sp->psc_smbtxrx = PSC_SMBTXRX_STP;
+ au_sync();
+ if (wait_master_done(adap))
+ return -EIO;
+
+ data = sp->psc_smbtxrx;
+ au_sync();
+ buf[i] = data;
+ return 0;
+}
+
+static int
+i2c_write(struct i2c_au1550_data *adap, unsigned char *buf,
+ unsigned int len)
+{
+ int i;
+ u32 data;
+ volatile psc_smb_t *sp;
+
+ if (len == 0)
+ return 0;
+
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+
+ i = 0;
+ while (i < (len-1)) {
+ data = buf[i];
+ sp->psc_smbtxrx = data;
+ au_sync();
+ if (wait_ack(adap))
+ return -EIO;
+ i++;
+ }
+
+ /* The last byte has to indicate transfer done.
+ */
+ data = buf[i];
+ data |= PSC_SMBTXRX_STP;
+ sp->psc_smbtxrx = data;
+ au_sync();
+ if (wait_master_done(adap))
+ return -EIO;
+ return 0;
+}
+
+static int
+au1550_xfer(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs, int num)
+{
+ struct i2c_au1550_data *adap = i2c_adap->algo_data;
+ struct i2c_msg *p;
+ int i, err = 0;
+
+ for (i = 0; !err && i < num; i++) {
+ p = &msgs[i];
+ err = do_address(adap, p->addr, p->flags & I2C_M_RD);
+ if (err || !p->len)
+ continue;
+ if (p->flags & I2C_M_RD)
+ err = i2c_read(adap, p->buf, p->len);
+ else
+ err = i2c_write(adap, p->buf, p->len);
+ }
+
+ /* Return the number of messages processed, or the error code.
+ */
+ if (err == 0)
+ err = num;
+ return err;
+}
+
+static u32
+au1550_func(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C;
+}
+
+static struct i2c_algorithm au1550_algo = {
+ .name = "Au1550 algorithm",
+ .id = I2C_ALGO_AU1550,
+ .master_xfer = au1550_xfer,
+ .functionality = au1550_func,
+};
+
+/*
+ * registering functions to load algorithms at runtime
+ * Prior to calling us, the 50MHz clock frequency and routing
+ * must have been set up for the PSC indicated by the adapter.
+ */
+int
+i2c_au1550_add_bus(struct i2c_adapter *i2c_adap)
+{
+ struct i2c_au1550_data *adap = i2c_adap->algo_data;
+ volatile psc_smb_t *sp;
+ u32 stat;
+
+ i2c_adap->algo = &au1550_algo;
+
+ /* Now, set up the PSC for SMBus PIO mode.
+ */
+ sp = (volatile psc_smb_t *)(adap->psc_base);
+ sp->psc_ctrl = PSC_CTRL_DISABLE;
+ au_sync();
+ sp->psc_sel = PSC_SEL_PS_SMBUSMODE;
+ sp->psc_smbcfg = 0;
+ au_sync();
+ sp->psc_ctrl = PSC_CTRL_ENABLE;
+ au_sync();
+ do {
+ stat = sp->psc_smbstat;
+ au_sync();
+ } while ((stat & PSC_SMBSTAT_SR) == 0);
+
+ sp->psc_smbcfg = (PSC_SMBCFG_RT_FIFO8 | PSC_SMBCFG_TT_FIFO8 |
+ PSC_SMBCFG_DD_DISABLE);
+
+ /* Divide by 8 to get a 6.25 MHz clock. The later protocol
+ * timings are based on this clock.
+ */
+ sp->psc_smbcfg |= PSC_SMBCFG_SET_DIV(PSC_SMBCFG_DIV8);
+ sp->psc_smbmsk = PSC_SMBMSK_ALLMASK;
+ au_sync();
+
+ /* Set the protocol timer values. See Table 71 in the
+ * Au1550 Data Book for standard timing values.
+ */
+ sp->psc_smbtmr = PSC_SMBTMR_SET_TH(0) | PSC_SMBTMR_SET_PS(15) | \
+ PSC_SMBTMR_SET_PU(15) | PSC_SMBTMR_SET_SH(15) | \
+ PSC_SMBTMR_SET_SU(15) | PSC_SMBTMR_SET_CL(15) | \
+ PSC_SMBTMR_SET_CH(15);
+ au_sync();
+
+ sp->psc_smbcfg |= PSC_SMBCFG_DE_ENABLE;
+ do {
+ stat = sp->psc_smbstat;
+ au_sync();
+ } while ((stat & PSC_SMBSTAT_DR) == 0);
+
+ return i2c_add_adapter(i2c_adap);
+}
+
+
+int
+i2c_au1550_del_bus(struct i2c_adapter *adap)
+{
+ return i2c_del_adapter(adap);
+}
+
+static int
+pb1550_reg(struct i2c_client *client)
+{
+ return 0;
+}
+
+static int
+pb1550_unreg(struct i2c_client *client)
+{
+ return 0;
+}
+
+static struct i2c_au1550_data pb1550_i2c_info = {
+ SMBUS_PSC_BASE, 200, 200
+};
+
+static struct i2c_adapter pb1550_board_adapter = {
+ name: "pb1550 adapter",
+ id: I2C_HW_AU1550_PSC,
+ algo: NULL,
+ algo_data: &pb1550_i2c_info,
+ client_register: pb1550_reg,
+ client_unregister: pb1550_unreg,
+};
+
+/* BIG hack to support the control interface on the Wolfson WM8731
+ * audio codec on the Pb1550 board. We get an address and two data
+ * bytes to write, create an i2c message, and send it across the
+ * i2c transfer function. We do this here because we have access to
+ * the i2c adapter structure.
+ */
+static struct i2c_msg wm_i2c_msg; /* We don't want this stuff on the stack */
+static u8 i2cbuf[2];
+
+int
+pb1550_wm_codec_write(u8 addr, u8 reg, u8 val)
+{
+ wm_i2c_msg.addr = addr;
+ wm_i2c_msg.flags = 0;
+ wm_i2c_msg.buf = i2cbuf;
+ wm_i2c_msg.len = 2;
+ i2cbuf[0] = reg;
+ i2cbuf[1] = val;
+
+ return pb1550_board_adapter.algo->master_xfer(&pb1550_board_adapter, &wm_i2c_msg, 1);
+}
+
+static int __init
+i2c_au1550_init(void)
+{
+ printk(KERN_INFO "Au1550 I2C: ");
+
+ /* This is where we would set up a 50MHz clock source
+ * and routing. On the Pb1550, the SMBus is PSC2, which
+ * uses a shared clock with USB. This has been already
+ * configured by Yamon as a 48MHz clock, close enough
+ * for our work.
+ */
+ if (i2c_au1550_add_bus(&pb1550_board_adapter) < 0) {
+ printk("failed to initialize.\n");
+ return -ENODEV;
+ }
+
+ printk("initialized.\n");
+ return 0;
+}
+
+static void __exit
+i2c_au1550_exit(void)
+{
+ i2c_au1550_del_bus(&pb1550_board_adapter);
+}
+
+MODULE_AUTHOR("Dan Malek, Embedded Edge, LLC.");
+MODULE_DESCRIPTION("SMBus adapter Alchemy pb1550");
+MODULE_LICENSE("GPL");
+
+module_init (i2c_au1550_init);
+module_exit (i2c_au1550_exit);