From 2d405ec5fdd5b6848beb820301d4fcaa3e2c4159 Mon Sep 17 00:00:00 2001 From: Boris BREZILLON Date: Sat, 13 Sep 2014 01:23:59 +0200 Subject: [PATCH] mtd: nand: atmel_nand: retrieve NFC clock Retrieve the NFC clock to make sure it is enabled. Make that optional to ensure compatibility with previous device trees but document it as mandatory so newer device trees will include it. Signed-off-by: Boris BREZILLON Signed-off-by: Alexandre Belloni Acked-by: Josh Wu Signed-off-by: Brian Norris --- .../devicetree/bindings/mtd/atmel-nand.txt | 2 ++ drivers/mtd/nand/atmel_nand.c | 25 +++++++++++++++++++ 2 files changed, 27 insertions(+) diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt b/Documentation/devicetree/bindings/mtd/atmel-nand.txt index c4728839d0c1..6edc3b616e98 100644 --- a/Documentation/devicetree/bindings/mtd/atmel-nand.txt +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt @@ -36,6 +36,7 @@ Optional properties: - reg : should specify the address and size used for NFC command registers, NFC registers and NFC Sram. NFC Sram address and size can be absent if don't want to use it. + - clocks: phandle to the peripheral clock - Optional properties: - atmel,write-by-sram: boolean to enable NFC write by sram. @@ -98,6 +99,7 @@ nand0: nand@40000000 { compatible = "atmel,sama5d3-nfc"; #address-cells = <1>; #size-cells = <1>; + clocks = <&hsmc_clk> reg = < 0x70000000 0x10000000 /* NFC Command Registers */ 0xffffc000 0x00000070 /* NFC HSMC regs */ diff --git a/drivers/mtd/nand/atmel_nand.c b/drivers/mtd/nand/atmel_nand.c index 9c5f717bda54..d1e502f8dbd0 100644 --- a/drivers/mtd/nand/atmel_nand.c +++ b/drivers/mtd/nand/atmel_nand.c @@ -27,6 +27,7 @@ * */ +#include #include #include #include @@ -96,6 +97,8 @@ struct atmel_nfc { bool use_nfc_sram; bool write_by_sram; + struct clk *clk; + bool is_initialized; struct completion comp_ready; struct completion comp_cmd_done; @@ -2248,6 +2251,7 @@ static int atmel_nand_nfc_probe(struct platform_device *pdev) { struct atmel_nfc *nfc = &nand_nfc; struct resource *nfc_cmd_regs, *nfc_hsmc_regs, *nfc_sram; + int ret; nfc_cmd_regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); nfc->base_cmd_regs = devm_ioremap_resource(&pdev->dev, nfc_cmd_regs); @@ -2279,8 +2283,28 @@ static int atmel_nand_nfc_probe(struct platform_device *pdev) nfc_writel(nfc->hsmc_regs, IDR, 0xffffffff); nfc_readl(nfc->hsmc_regs, SR); /* clear the NFC_SR */ + nfc->clk = devm_clk_get(&pdev->dev, NULL); + if (!IS_ERR(nfc->clk)) { + ret = clk_prepare_enable(nfc->clk); + if (ret) + return ret; + } else { + dev_warn(&pdev->dev, "NFC clock missing, update your Device Tree"); + } + nfc->is_initialized = true; dev_info(&pdev->dev, "NFC is probed.\n"); + + return 0; +} + +static int atmel_nand_nfc_remove(struct platform_device *pdev) +{ + struct atmel_nfc *nfc = &nand_nfc; + + if (!IS_ERR(nfc->clk)) + clk_disable_unprepare(nfc->clk); + return 0; } @@ -2297,6 +2321,7 @@ static struct platform_driver atmel_nand_nfc_driver = { .of_match_table = of_match_ptr(atmel_nand_nfc_match), }, .probe = atmel_nand_nfc_probe, + .remove = atmel_nand_nfc_remove, }; static struct platform_driver atmel_nand_driver = {