[PATCH 13/23] AT91 DMA OF support
Richard Genoud
richard.genoud at gmail.com
Tue Aug 14 09:49:27 EDT 2012
Signed-off-by: Richard Genoud <richard.genoud at gmail.com>
---
arch/arm/mach-at91/include/mach/at_hdmac.h | 1 +
drivers/of/Kconfig | 4 +
drivers/of/Makefile | 1 +
drivers/of/of_atmel.c | 112 ++++++++++++++++++++++++++++
include/linux/of_atmel.h | 29 +++++++
5 files changed, 147 insertions(+), 0 deletions(-)
create mode 100644 drivers/of/of_atmel.c
create mode 100644 include/linux/of_atmel.h
diff --git a/arch/arm/mach-at91/include/mach/at_hdmac.h b/arch/arm/mach-at91/include/mach/at_hdmac.h
index cab0997..35667bd 100644
--- a/arch/arm/mach-at91/include/mach/at_hdmac.h
+++ b/arch/arm/mach-at91/include/mach/at_hdmac.h
@@ -52,6 +52,7 @@ struct at_dma_slave {
#define ATC_LOCK_IF_L_CHUNK (0x0 << 22)
#define ATC_LOCK_IF_L_BUFFER (0x1 << 22)
#define ATC_AHB_PROT_MASK (0x7 << 24) /* AHB Protection */
+#define ATC_AHB_PROT(h) (((h) << 24) && ATC_AHB_PROT_MASK)
#define ATC_FIFOCFG_MASK (0x3 << 28) /* FIFO Request Configuration */
#define ATC_FIFOCFG_LARGESTBURST (0x0 << 28)
#define ATC_FIFOCFG_HALFFIFO (0x1 << 28)
diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
index dfba3e6..4667960 100644
--- a/drivers/of/Kconfig
+++ b/drivers/of/Kconfig
@@ -83,4 +83,8 @@ config OF_MTD
depends on MTD
def_bool y
+config OF_ATMEL
+ depends on AT_HDMAC
+ def_bool y
+
endmenu # OF
diff --git a/drivers/of/Makefile b/drivers/of/Makefile
index e027f44..897de3b 100644
--- a/drivers/of/Makefile
+++ b/drivers/of/Makefile
@@ -11,3 +11,4 @@ obj-$(CONFIG_OF_MDIO) += of_mdio.o
obj-$(CONFIG_OF_PCI) += of_pci.o
obj-$(CONFIG_OF_PCI_IRQ) += of_pci_irq.o
obj-$(CONFIG_OF_MTD) += of_mtd.o
+obj-$(CONFIG_OF_ATMEL) += of_atmel.o
diff --git a/drivers/of/of_atmel.c b/drivers/of/of_atmel.c
new file mode 100644
index 0000000..bcd3c54a
--- /dev/null
+++ b/drivers/of/of_atmel.c
@@ -0,0 +1,112 @@
+/*
+ * Copyright (C) 2012 Richard Genoud, Paratronic S.A.
+ * <richard.genoud at gmail.com>
+ *
+ * Atmel specifics OF helpers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/printk.h>
+#include <linux/byteorder/generic.h>
+#include <mach/at_hdmac.h>
+#include <linux/of.h>
+
+static int of_dev_node_match(struct device *dev, void *data)
+{
+ return dev->of_node == data;
+}
+
+/**
+ * of_create_at_dma_slave - Alloc and initialize the struct at_dma_slave
+ * @np: pointer to node to create the struct for
+ * @bus: pointer to the bus type of the DMA device.
+ *
+ * Returns pointer to created DMA slave structure, or NULL in case of error.
+ */
+struct at_dma_slave *of_create_at_dma_slave(struct device_node *np,
+ struct bus_type *bus)
+{
+ struct at_dma_slave *atslave;
+ struct device_node *n;
+ struct property *prop;
+ const __be32 *dma_list;
+ phandle phandle;
+ int size;
+ int err = -1;
+ u32 val;
+
+ atslave = kzalloc(sizeof(struct at_dma_slave), GFP_KERNEL);
+ if (unlikely(!atslave)) {
+ pr_err("cannot allocate memory\n");
+ goto error;
+ }
+
+ atslave->cfg |= of_property_read_bool(np, "atc_src_rep") ? ATC_SRC_REP : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_dst_rep") ? ATC_DST_REP : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_src_h2sel_hw") ? ATC_SRC_H2SEL_HW : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_dst_h2sel_hw") ? ATC_DST_H2SEL_HW : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_sod") ? ATC_SOD : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_lock_if") ? ATC_LOCK_IF : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_lock_b") ? ATC_LOCK_B : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_lock_if_l") ? ATC_LOCK_IF_L : 0;
+ atslave->cfg |= of_property_read_bool(np, "atc_lock_if_l_buffer") ? ATC_LOCK_IF_L_BUFFER : 0;
+ if (of_property_read_bool(np, "atc_fifocfg_halffifo"))
+ atslave->cfg = (atslave->cfg & ~ATC_FIFOCFG_MASK) | ATC_FIFOCFG_HALFFIFO;
+ if (of_property_read_bool(np, "atc_fifocfg_enoughspace"))
+ atslave->cfg = (atslave->cfg & ~ATC_FIFOCFG_MASK) | ATC_FIFOCFG_ENOUGHSPACE;
+ if (of_property_read_bool(np, "atc_fifocfg_largestburst"))
+ atslave->cfg = (atslave->cfg & ~ATC_FIFOCFG_MASK) | ATC_FIFOCFG_LARGESTBURST;
+ if (!of_property_read_u32(np, "atc_ahb_prot", &val))
+ atslave->cfg |= ATC_AHB_PROT(val);
+ if (!of_property_read_u32(np, "atc_src_per", &val))
+ atslave->cfg |= ATC_SRC_PER(val);
+ if (!of_property_read_u32(np, "atc_dst_per", &val))
+ atslave->cfg |= ATC_DST_PER(val);
+
+ /* we need to associate the wanted dma struct device to
+ * atslave->dma_dev. This is needed when searching for
+ * a free dma channel
+ */
+ prop = of_find_property(np, "dma", &size);
+ if (!prop) {
+ pr_err("can't find the dma child node\n");
+ goto error;
+ }
+ dma_list = prop->value;
+ size /= sizeof(*dma_list);
+ if (size != 1) {
+ pr_err("only one dma handle is supported\n");
+ goto error;
+ }
+
+ phandle = be32_to_cpup(dma_list);
+ n = of_find_node_by_phandle(phandle);
+ if (!n) {
+ pr_err("unable to find dma device: invalid phandle %s\n",
+ prop->name);
+ goto error;
+ }
+
+ atslave->dma_dev = bus_find_device(bus, NULL, n, of_dev_node_match);
+ if (!atslave->dma_dev) {
+ pr_err("can't find struct device for DMA %s\n", prop->name);
+ goto error;
+ }
+
+ pr_debug("DMA cfg register=0x%x DMA device path=%s\n",
+ atslave->cfg, prop->name);
+ err = 0;
+error:
+ if (err)
+ kfree(atslave);
+ return atslave;
+}
+EXPORT_SYMBOL_GPL(of_create_at_dma_slave);
+
diff --git a/include/linux/of_atmel.h b/include/linux/of_atmel.h
new file mode 100644
index 0000000..256f336
--- /dev/null
+++ b/include/linux/of_atmel.h
@@ -0,0 +1,29 @@
+#ifndef _LINUX_OF_ATMEL_H
+#define _LINUX_OF_ATMEL_H
+/*
+ * Copyright (C) 2012 Richard Genoud, Paratronic S.A.
+ * <richard.genoud at gmail.com>
+ *
+ * Atmel specifics OF helpers
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+#include <linux/of.h>
+#include <linux/device.h>
+#include <mach/at_hdmac.h>
+
+#ifdef CONFIG_OF_ATMEL
+extern struct at_dma_slave *of_create_at_dma_slave(struct device_node *np,
+ struct bus_type *bus);
+#else
+static struct at_dma_slave *of_create_at_dma_slave(struct device_node *np,
+ struct bus_type *bus)
+{
+ return NULL;
+}
+#endif /* CONFIG_OF_ATMEL */
+
+#endif /* _LINUX_OF_ATMEL_H */
--
1.7.2.5
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