diff options
Diffstat (limited to 'target/linux/gemini/patches-4.19/0006-mtd-physmap_of_gemini-Handle-pin-control.patch')
| -rw-r--r-- | target/linux/gemini/patches-4.19/0006-mtd-physmap_of_gemini-Handle-pin-control.patch | 194 |
1 files changed, 194 insertions, 0 deletions
diff --git a/target/linux/gemini/patches-4.19/0006-mtd-physmap_of_gemini-Handle-pin-control.patch b/target/linux/gemini/patches-4.19/0006-mtd-physmap_of_gemini-Handle-pin-control.patch new file mode 100644 index 0000000000..47aa38a6ab --- /dev/null +++ b/target/linux/gemini/patches-4.19/0006-mtd-physmap_of_gemini-Handle-pin-control.patch @@ -0,0 +1,194 @@ +From 8e5e628a9de439d02914b85a48e1ac3e04ea486a Mon Sep 17 00:00:00 2001 +From: Linus Walleij <linus.walleij@linaro.org> +Date: Thu, 11 Oct 2018 20:03:49 +0200 +Subject: [PATCH 06/18] mtd: physmap_of_gemini: Handle pin control + +This enables the complex mapping for the Gemini and kicks in +custom read/write functions that will wrap the existing +simple functions in calls to enable/disable the parallel +flash pins using pin controls. + +This is necessary on some hardware such as the D-Link +DIR-685 where all flash pins are patched in/out at the same +time, but some of the flash pins are in practice unused by +the flash and have anyway been reused as GPIO. + +This concerns specifically CE1 on the Gemini. There is only +one flash chip, so only CE0 is used, and the line for CE1 +has been reused as chip select for the emulated SPI port +connected to the display. If we try to use the same lines +for flash and GPIO at the same time, one of them will loose: +the GPIO line will disappear because it gets disconnected +from the pin when the flash group is muxed out. + +Fix this by introducing two pin control states named simply +"enabled" and "disabled" and only enable the flash lines +when absolutely necessary (during read/write/copy). This +way, they are available for GPIO at all other times and +the display works. + +Collect all the state variables in a struct named +struct gemini_flash and allocate this struct at probe +time. + +Signed-off-by: Linus Walleij <linus.walleij@linaro.org> +--- + drivers/mtd/maps/Kconfig | 1 + + drivers/mtd/maps/physmap_of_gemini.c | 105 ++++++++++++++++++++++++++- + 2 files changed, 105 insertions(+), 1 deletion(-) + +diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig +index afb36bff13a7..00efbf246849 100644 +--- a/drivers/mtd/maps/Kconfig ++++ b/drivers/mtd/maps/Kconfig +@@ -89,6 +89,7 @@ config MTD_PHYSMAP_OF_GEMINI + depends on MTD_PHYSMAP_OF + depends on MFD_SYSCON + default ARCH_GEMINI ++ select MTD_COMPLEX_MAPPINGS + help + This provides some extra DT physmap parsing for the Gemini + platforms, some detection and setting up parallel mode on the +diff --git a/drivers/mtd/maps/physmap_of_gemini.c b/drivers/mtd/maps/physmap_of_gemini.c +index 830b1b7e702b..7c2b67460192 100644 +--- a/drivers/mtd/maps/physmap_of_gemini.c ++++ b/drivers/mtd/maps/physmap_of_gemini.c +@@ -10,9 +10,11 @@ + #include <linux/of.h> + #include <linux/of_device.h> + #include <linux/mtd/map.h> ++#include <linux/mtd/xip.h> + #include <linux/mfd/syscon.h> + #include <linux/regmap.h> + #include <linux/bitops.h> ++#include <linux/pinctrl/consumer.h> + #include "physmap_of_gemini.h" + + /* +@@ -49,6 +51,77 @@ static const struct of_device_id syscon_match[] = { + { }, + }; + ++struct gemini_flash { ++ struct device *dev; ++ struct pinctrl *p; ++ struct pinctrl_state *enabled_state; ++ struct pinctrl_state *disabled_state; ++}; ++ ++/* Static local state */ ++static struct gemini_flash *gf; ++ ++static void gemini_flash_enable_pins(void) ++{ ++ int ret; ++ ++ if (IS_ERR(gf->enabled_state)) ++ return; ++ ret = pinctrl_select_state(gf->p, gf->enabled_state); ++ if (ret) ++ dev_err(gf->dev, "failed to enable pins\n"); ++} ++ ++static void gemini_flash_disable_pins(void) ++{ ++ int ret; ++ ++ if (IS_ERR(gf->disabled_state)) ++ return; ++ ret = pinctrl_select_state(gf->p, gf->disabled_state); ++ if (ret) ++ dev_err(gf->dev, "failed to disable pins\n"); ++} ++ ++static map_word __xipram gemini_flash_map_read(struct map_info *map, ++ unsigned long ofs) ++{ ++ map_word __xipram ret; ++ ++ gemini_flash_enable_pins(); ++ ret = inline_map_read(map, ofs); ++ gemini_flash_disable_pins(); ++ ++ return ret; ++} ++ ++static void __xipram gemini_flash_map_write(struct map_info *map, ++ const map_word datum, ++ unsigned long ofs) ++{ ++ gemini_flash_enable_pins(); ++ inline_map_write(map, datum, ofs); ++ gemini_flash_disable_pins(); ++} ++ ++static void __xipram gemini_flash_map_copy_from(struct map_info *map, ++ void *to, unsigned long from, ++ ssize_t len) ++{ ++ gemini_flash_enable_pins(); ++ inline_map_copy_from(map, to, from, len); ++ gemini_flash_disable_pins(); ++} ++ ++static void __xipram gemini_flash_map_copy_to(struct map_info *map, ++ unsigned long to, ++ const void *from, ssize_t len) ++{ ++ gemini_flash_enable_pins(); ++ inline_map_copy_to(map, to, from, len); ++ gemini_flash_disable_pins(); ++} ++ + int of_flash_probe_gemini(struct platform_device *pdev, + struct device_node *np, + struct map_info *map) +@@ -62,6 +135,11 @@ int of_flash_probe_gemini(struct platform_device *pdev, + if (!of_device_is_compatible(np, "cortina,gemini-flash")) + return 0; + ++ gf = devm_kzalloc(dev, sizeof(*gf), GFP_KERNEL); ++ if (!gf) ++ return -ENOMEM; ++ gf->dev = dev; ++ + rmap = syscon_regmap_lookup_by_phandle(np, "syscon"); + if (IS_ERR(rmap)) { + dev_err(dev, "no syscon\n"); +@@ -96,7 +174,32 @@ int of_flash_probe_gemini(struct platform_device *pdev, + map->bankwidth * 8); + } + +- dev_info(&pdev->dev, "initialized Gemini-specific physmap control\n"); ++ gf->p = devm_pinctrl_get(dev); ++ if (IS_ERR(gf->p)) { ++ dev_err(dev, "no pinctrl handle\n"); ++ ret = PTR_ERR(gf->p); ++ return ret; ++ } ++ ++ gf->enabled_state = pinctrl_lookup_state(gf->p, "enabled"); ++ if (IS_ERR(gf->enabled_state)) ++ dev_err(dev, "no enabled pin control state\n"); ++ ++ gf->disabled_state = pinctrl_lookup_state(gf->p, "disabled"); ++ if (IS_ERR(gf->enabled_state)) { ++ dev_err(dev, "no disabled pin control state\n"); ++ } else { ++ ret = pinctrl_select_state(gf->p, gf->disabled_state); ++ if (ret) ++ dev_err(gf->dev, "failed to disable pins\n"); ++ } ++ ++ map->read = gemini_flash_map_read; ++ map->write = gemini_flash_map_write; ++ map->copy_from = gemini_flash_map_copy_from; ++ map->copy_to = gemini_flash_map_copy_to; ++ ++ dev_info(dev, "initialized Gemini-specific physmap control\n"); + + return 0; + } +-- +2.19.2 + |