From 0c0ef9ea6f3f0d5979dc7b094b0a184c1a94716b Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Sat, 14 Sep 2019 14:02:55 -0700 Subject: [PATCH] hwrng: omap3-rom - Fix missing clock by probing with device tree MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 0ed266d7ae5e ("clk: ti: omap3: cleanup unnecessary clock aliases") removed old omap3 clock framework aliases but caused omap3-rom-rng to stop working with clock not found error. Based on discussions on the mailing list it was requested by Tero Kristo that it would be best to fix this issue by probing omap3-rom-rng using device tree to provide a proper clk property. The other option would be to add back the missing clock alias, but that does not help moving things forward with removing old legacy platform_data. Let's also add a proper device tree binding and keep it together with the fix. Cc: devicetree@vger.kernel.org Cc: Aaro Koskinen Cc: Adam Ford Cc: Pali Rohár Cc: Rob Herring Cc: Sebastian Reichel Cc: Tero Kristo Fixes: 0ed266d7ae5e ("clk: ti: omap3: cleanup unnecessary clock aliases") Reported-by: Aaro Koskinen Signed-off-by: Tony Lindgren Acked-by: Rob Herring Signed-off-by: Herbert Xu --- .../devicetree/bindings/rng/omap3_rom_rng.txt | 27 +++++++++++++++++++ arch/arm/boot/dts/omap3-n900.dts | 6 +++++ arch/arm/mach-omap2/pdata-quirks.c | 12 +-------- drivers/char/hw_random/omap3-rom-rng.c | 17 ++++++++++-- 4 files changed, 49 insertions(+), 13 deletions(-) create mode 100644 Documentation/devicetree/bindings/rng/omap3_rom_rng.txt diff --git a/Documentation/devicetree/bindings/rng/omap3_rom_rng.txt b/Documentation/devicetree/bindings/rng/omap3_rom_rng.txt new file mode 100644 index 000000000000..f315c9723bd2 --- /dev/null +++ b/Documentation/devicetree/bindings/rng/omap3_rom_rng.txt @@ -0,0 +1,27 @@ +OMAP ROM RNG driver binding + +Secure SoCs may provide RNG via secure ROM calls like Nokia N900 does. The +implementation can depend on the SoC secure ROM used. + +- compatible: + Usage: required + Value type: + Definition: must be "nokia,n900-rom-rng" + +- clocks: + Usage: required + Value type: + Definition: reference to the the RNG interface clock + +- clock-names: + Usage: required + Value type: + Definition: must be "ick" + +Example: + + rom_rng: rng { + compatible = "nokia,n900-rom-rng"; + clocks = <&rng_ick>; + clock-names = "ick"; + }; diff --git a/arch/arm/boot/dts/omap3-n900.dts b/arch/arm/boot/dts/omap3-n900.dts index 84a5ade1e865..63659880eeb3 100644 --- a/arch/arm/boot/dts/omap3-n900.dts +++ b/arch/arm/boot/dts/omap3-n900.dts @@ -155,6 +155,12 @@ pwms = <&pwm9 0 26316 0>; /* 38000 Hz */ }; + rom_rng: rng { + compatible = "nokia,n900-rom-rng"; + clocks = <&rng_ick>; + clock-names = "ick"; + }; + /* controlled (enabled/disabled) directly by bcm2048 and wl1251 */ vctcxo: vctcxo { compatible = "fixed-clock"; diff --git a/arch/arm/mach-omap2/pdata-quirks.c b/arch/arm/mach-omap2/pdata-quirks.c index b49ec3fbee4c..62cc90722848 100644 --- a/arch/arm/mach-omap2/pdata-quirks.c +++ b/arch/arm/mach-omap2/pdata-quirks.c @@ -262,14 +262,6 @@ static void __init am3517_evm_legacy_init(void) am35xx_emac_reset(); } -static struct platform_device omap3_rom_rng_device = { - .name = "omap3-rom-rng", - .id = -1, - .dev = { - .platform_data = rx51_secure_rng_call, - }, -}; - static void __init nokia_n900_legacy_init(void) { hsmmc2_internal_input_clk(); @@ -285,9 +277,6 @@ static void __init nokia_n900_legacy_init(void) pr_warn("RX-51: Not enabling ARM errata 430973 workaround\n"); pr_warn("Thumb binaries may crash randomly without this workaround\n"); } - - pr_info("RX-51: Registering OMAP3 HWRNG device\n"); - platform_device_register(&omap3_rom_rng_device); } } @@ -627,6 +616,7 @@ static struct of_dev_auxdata omap_auxdata_lookup[] = { OF_DEV_AUXDATA("ti,davinci_mdio", 0x5c030000, "davinci_mdio.0", NULL), OF_DEV_AUXDATA("ti,am3517-emac", 0x5c000000, "davinci_emac.0", &am35xx_emac_pdata), + OF_DEV_AUXDATA("nokia,n900-rom-rng", 0, NULL, rx51_secure_rng_call), /* McBSP modules with sidetone core */ #if IS_ENABLED(CONFIG_SND_SOC_OMAP_MCBSP) OF_DEV_AUXDATA("ti,omap3-mcbsp", 0x49022000, "49022000.mcbsp", &mcbsp_pdata), diff --git a/drivers/char/hw_random/omap3-rom-rng.c b/drivers/char/hw_random/omap3-rom-rng.c index 38b719017186..34e10f05545a 100644 --- a/drivers/char/hw_random/omap3-rom-rng.c +++ b/drivers/char/hw_random/omap3-rom-rng.c @@ -20,6 +20,8 @@ #include #include #include +#include +#include #include #define RNG_RESET 0x01 @@ -86,14 +88,18 @@ static int omap3_rom_rng_read(struct hwrng *rng, void *data, size_t max, bool w) static struct hwrng omap3_rom_rng_ops = { .name = "omap3-rom", - .read = omap3_rom_rng_read, }; static int omap3_rom_rng_probe(struct platform_device *pdev) { int ret = 0; - pr_info("initializing\n"); + omap3_rom_rng_ops.read = of_device_get_match_data(&pdev->dev); + if (!omap3_rom_rng_ops.read) { + dev_err(&pdev->dev, "missing rom code handler\n"); + + return -ENODEV; + } omap3_rom_rng_call = pdev->dev.platform_data; if (!omap3_rom_rng_call) { @@ -125,9 +131,16 @@ static int omap3_rom_rng_remove(struct platform_device *pdev) return 0; } +static const struct of_device_id omap_rom_rng_match[] = { + { .compatible = "nokia,n900-rom-rng", .data = omap3_rom_rng_read, }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, omap_rom_rng_match); + static struct platform_driver omap3_rom_rng_driver = { .driver = { .name = "omap3-rom-rng", + .of_match_table = omap_rom_rng_match, }, .probe = omap3_rom_rng_probe, .remove = omap3_rom_rng_remove,