Hi, > From: Kishon Vijay Abraham I [mailto:kis...@ti.com] > Sent: Monday, January 06, 2014 11:12 AM > > Hi, > > On Friday 20 December 2013 06:54 PM, Kamil Debski wrote: > > Add a new driver for the Exynos USB 2.0 PHY. The new driver uses the > > generic PHY framework. The driver includes support for the Exynos > 4x10 > > and 4x12 SoC families. > > > > Signed-off-by: Kamil Debski <k.deb...@samsung.com> > > Signed-off-by: Kyungmin Park <kyungmin.p...@samsung.com> > > --- > > .../devicetree/bindings/phy/samsung-phy.txt | 55 ++++ > > drivers/phy/Kconfig | 29 ++ > > drivers/phy/Makefile | 3 + > > drivers/phy/phy-exynos4210-usb2.c | 257 > ++++++++++++++++ > > drivers/phy/phy-exynos4212-usb2.c | 306 > ++++++++++++++++++++ > > drivers/phy/phy-samsung-usb2.c | 226 > +++++++++++++++ > > drivers/phy/phy-samsung-usb2.h | 67 +++++ > > 7 files changed, 943 insertions(+) > > create mode 100644 drivers/phy/phy-exynos4210-usb2.c > > create mode 100644 drivers/phy/phy-exynos4212-usb2.c > > create mode 100644 drivers/phy/phy-samsung-usb2.c > > create mode 100644 drivers/phy/phy-samsung-usb2.h > > > . > . > <snip> > . > . > > > diff --git a/drivers/phy/phy-samsung-usb2.h > > b/drivers/phy/phy-samsung-usb2.h new file mode 100644 index > > 0000000..ab89f91 > > --- /dev/null > > +++ b/drivers/phy/phy-samsung-usb2.h > > @@ -0,0 +1,67 @@ > > +/* > > + * Samsung SoC USB 1.1/2.0 PHY driver > > + * > > + * Copyright (C) 2013 Samsung Electronics Co., Ltd. > > + * Author: Kamil Debski <k.deb...@samsung.com> > > + * > > + * 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. > > + */ > > + > > +#ifndef _PHY_EXYNOS_USB2_H > > +#define _PHY_EXYNOS_USB2_H > > + > > +#include <linux/clk.h> > > +#include <linux/phy/phy.h> > > +#include <linux/device.h> > > +#include <linux/regmap.h> > > +#include <linux/spinlock.h> > > + > > +#define KHZ 1000 > > +#define MHZ (KHZ * KHZ) > > + > > +struct samsung_usb2_phy_driver; > > +struct samsung_usb2_phy_instance; > > +struct samsung_usb2_phy_config; > > + > > +struct samsung_usb2_phy_instance { > > + const struct samsung_usb2_common_phy *cfg; > > + struct clk *clk; > > + struct phy *phy; > > + struct samsung_usb2_phy_driver *drv; > > + unsigned long rate; > > + u32 clk_reg_val; > > + bool enabled; > > +}; > > + > > +struct samsung_usb2_phy_driver { > > + const struct samsung_usb2_phy_config *cfg; > > + struct clk *clk; > > + struct device *dev; > > + void __iomem *reg_phy; > > + struct regmap *reg_pmu; > > + struct regmap *reg_sys; > > + spinlock_t lock; > > + struct samsung_usb2_phy_instance instances[0]; > > I think having instances as array here would allocate more space while > allocating 'samsung_usb2_phy_driver' in 'samsung_usb2_phy_probe'. >
I am not sure if I understand you correctly here. Maybe I will explain what I intended to write. An array with size 0 at the end of a structure takes no space in the structure. The benefit of using it is that after the structure one can allocate a number of the array elements and address them easily. Another option would be placing pointer in the samsung_usb2_phy_instance and allocate memory separately, but this would involve two allocations and a pointer would be always present in the structure. Best wishes, -- Kamil Debski Samsung R&D Institute Poland -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html