msm: add gpiomux api for gpio multiplex & configuration.

Add the 'gpiomux' api, which addresses the following shortcomings
of existing tlmm api:

- gpio power-collapse, which is managed by a peripheral processor on
  other targets, must be managed by the application processor on the 8x60.
- The enable/disable flag of the legacy gpio_tlmm_config api
  is not applicable on the 8x60, and causes confusion.
- The gpio 'direction' bits are meaningless for all func_sel
  configurations except for generic-gpio mode (func_sel 0), in which
  case the gpio_direction_* functions should be used.  Having these
  bits in the tlmm api leads to confusion and misuse of the gpiolib
  api, and they have been removed in gpiomux.
- The functional api of the legacy system ran contrary to the typical
  use-case, which is a single massive configuration at boot.  Rather
  than forcing hundreds of 'config' function calls, the new api
  allows data to be configured with a single table.

gpiomux_get and gpiomux_put are meant to be called automatically
when gpio_request and gpio_free are called, giving automatic
gpiomux/tlmm control to those drivers/lines with simple
power profiles - in the simplest cases, an entry in the gpiomux table
and the correct usage of gpiolib is all that is required to get proper
gpio power control.

Signed-off-by: Gregory Bean <gbean@codeaurora.org>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>

1 files changed, 33 insertions, 0 deletions

diff --git a/arch/arm/mach-msm/gpiomux-v1.c b/arch/arm/mach-msm/gpiomux-v1.c
new file mode 100644
index 00000000000..27de2abd714
--- /dev/null
+++ b/arch/arm/mach-msm/gpiomux-v1.c
@@ -0,0 +1,33 @@
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * 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., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+#include <linux/kernel.h>
+#include "gpiomux.h"
+#include "proc_comm.h"
+
+void __msm_gpiomux_write(unsigned gpio, gpiomux_config_t val)
+{
+	unsigned tlmm_config  = (val & ~GPIOMUX_CTL_MASK) |
+				((gpio & 0x3ff) << 4);
+	unsigned tlmm_disable = 0;
+	int rc;
+
+	rc = msm_proc_comm(PCOM_RPC_GPIO_TLMM_CONFIG_EX,
+			   &tlmm_config, &tlmm_disable);
+	if (rc)
+		pr_err("%s: unexpected proc_comm failure %d: %08x %08x\n",
+		       __func__, rc, tlmm_config, tlmm_disable);
+}